Paleobiogeography of Miocene to Pliocene Equinae of North America: a Phylogenetic

Home , Aletomeryx, Astrohippus, Bone Valley Formation, Calippus (genus), Chalicothere, Cormohipparion

Paleobiogeography of Miocene to Pliocene Equinae of North America: A Phylogenetic

Biogeographic and Niche Modeling Approach

A thesis presented to

the faculty of

the College of Arts and Sciences of Ohio University

In partial fulfillment

of the requirements for the degree

Master of Science

Kaitlin Clare Maguire

June 2008 2

This thesis titled

Paleobiogeography of Miocene to Pliocene Equinae of North America: A Phylogenetic

Biogeographic and Niche Modeling Approach

KAITLIN CLARE MAGUIRE

has been approved for

the Department of Geological Sciences

and the College of Arts and Sciences by

Alycia L. Stigall

Assistant Professor of Geological Sciences

Benjamin M. Ogles

Dean, College of Arts and Sciences 3

ABSTRACT

MAGUIRE, KAITLIN CLARE, M.S., June 2008, Geological Sciences

Paleobiogeography of Miocene to Pliocene Equinae of North America: A Phylogenetic

Biogeographic and Niche Modeling Approach (195 pp.)

Director of Thesis: Alycia L. Stigall

The biogeography and evolution of the subfamily Equinae is examined using two

separate but related analyses, phylogenetic biogeography and ecological niche modeling.

The evolution of Equinae is a classic example of an adaptive radiation during a time of

environmental change. Both analyses employed here examine the biogeography of the

equine species to interpret how environmental and historical variables led to the rise and

fall of this clade. Results determine climate change is the primary factor driving the

radiation of Equinae and geodispersal is the dominant mode of speciation between regions of North America. A case study in the Great Plains indicates distributional patterns are more patchy during the middle Miocene when speciation rates are high than in the late Miocene, when the clade is in decline. Statistical results and distributional patterns show equine species tracked their preferred habitat throughout North America as climate changed in the Miocene.

Approved: ______

Alycia L. Stigall

Assistant Professor of Geological Sciences 4

ACKNOWLEDGMENTS

The completion of this thesis would not have been possible without the help and guidance of several people. I would like to thank the following people for providing data:

B.H. Passey, J.D. Damuth, J.R. Thomasson and a special thanks to G.J. Retallack. I would also like to thank C.M. Janis and Y. Wang for pointing me in the right direction for data, R.C. Hulbert and J. Alroy for clarification with phylogenetic relationships in the clade, and R. Purdy for access to the collections at NMNH. A big thanks to Chris Dobel for assisting me with data collection.

This research was funded by an Ohio University Geological Sciences Graduate

Alumni Research Grant, GSA Grants-in-Aid Award, and OHIO Center for Ecology and

Evolutionary Studies Fellowship.

I would especially like to thank my advisor, Alycia Stigall for all of her help, guidance and support that has not only made me a better student, but a better

professional. Thank you also to my committee members, Dan Hembree, Pat O’Connor

and Keith Milam for reviewing parts of this thesis intended for publication and for all of

their help and support along the way. 5

TABLE OF CONTENTS

Page

Abstract...... 3

Acknowledgments...... 4

List of Tables ...... 8

List of Figures...... 9

Chapter 1: Introduction...... 10

References...... 14

Chapter 2: Paleobiogeography of Miocene Equinae of North America: A phylogenetic biogeographic analysis of the relative roles of climate, vicariance, and dispersal ...... 16

Abstract...... 16

Introduction...... 17

Geologic and Paleoclimatic Framework...... 21

Evolutionary Framework ...... 23

Materials and Methods...... 26

Taxa and geographic regions ...... 26

Analytical Biogeographic Method ...... 28

Results...... 30

Speciation Patterns ...... 30

Biogeographic Area Analysis ...... 31

Discussion...... 33

Distributional Patterns ...... 33 6

Vicariance Patterns ...... 37

Geodispersal Patterns...... 40

Comparison and Synthesis...... 42

Conclusions...... 43

References...... 45

CHAPTER 3: Distribution of fossil horses in the Great Plains during the Miocene and

Pliocene: An ecological niche modeling approach...... 52

Abstract...... 52

Introduction...... 53

Methods ...... 57

Geographic and Stratigraphic Intervals...... 57

Species Occurrence Information...... 63

Environmental Data...... 64

Creation of Environmental Layers...... 72

Distribution Modeling...... 73

Biogeographic Analyses...... 77

Results and Discussion ...... 81

Habitat Fragmentation ...... 81

Habitat Tracking...... 83

Range Size vs. Survival ...... 89

Regional Trends ...... 92

Conclusions...... 95 7

References...... 97

Chapter 4: Conclusion...... 106

References...... 109

APPENDIX A: Vicariance and geodispersal matrix ...... 110

APPENDIX B: Published references for geographic location data...... 112

APPENDIX C: Species occurrence data for the great plains ...... 124

APPENDIX D: Original environmental data...... 143

APPENDIX E: Predicted species distribution maps...... 186

LIST OF TABLES

Page

Table 1.Species modeled in the middle and late time slices...... 58

Table 2.Environmental data refereneces by variable...... 59

Table 3.Environmental data for each grid box in the middle time slice...... 69

Table 4.Environmental data for each grid box in the late time slice ...... 70

Table 5.Geographic ranges predicted for species from GARP modeling...... 79

Table 6.Two-Sample T-Test comparing number of discrete populations per time slice.. 83

Table 7.Two-Sample T-Test comparing the area of a species’ geographic range in the Southern Great Plains per time slice...... 85

Table 8.Linear Regression Analysis of species longevity and the area of a species’ geographic range...... 90

Table 9.Kruskal Wallis Test comparing the area of a species’ geographic range verses species survivall across the Barstovian/Clarendonian Boundary ...... 90

Table 10. Kruskal Wallis Test comparing the area of a species’ geographic range verses species survivall across the Clarendonian/Hemphillian Boundary...... 91

Table 11. Kruskal Wallis Test comparing the area of a species’ geographic range verses species survivall across the Hemphillian/Blancan Boundary ...... 91

LIST OF FIGURES

Page Figure 1. Temporally calibrated cladogram of the Equinae...... 18

Figure 2. Endemic geographic areas of the subfamily Equinae in North America analyzed in this study...... 19

Figure 3. Area cladogram of the Equinae clade based on phylogenetic topology in Figure 1...... 19

Figure 4. Vicariance and geodispersal area cladograms derived from Lieberman-modified Brooks Parsimony Analysis...... 19

Figure 5. Great Plains study area with 1° x 1° grid boxes overlain...... 19

Figure 6. Examples of environmental variable interpolations...... 19

Figure 7. GARP predicted species distribution maps for Pseudhipparion gratum, Nannippus lenticularis, Nannippus aztecus, and Pseudhipparion peninsulatus...... 19

Figure 8. GARP predicted distribution maps for Astrohippus ansae and Dinohippus interpolatus in the late time slice...... 19

Figure 9. GARP prediction maps for Cormohipparion occidentale...... 19

Figure 10. GARP predicted species distribution maps for P. mirabilis, and P. pernix and P. nobilis...... 19

CHAPTER 1: INTRODUCTION

This thesis is a compilation of two separate, but related, analyses on the

biogeography and evolution of Miocene and Pliocene fossil horses of the subfamily

Equinae of North America. The Miocene record of fossil horse species includes a

dramatic radiation in the number of species that has long been interpreted as a classic

example of an adaptive radiation driven by changes in the climatic and vegetative regime

during the Miocene (e.g., Simpson, 1951; MacFadden and Hulbert, 1988; Hulbert, 1993;

Webb et al., 1995). While the evolutionary patterns in terms of phylogenetic

relationships are well known (MacFadden, 1992; Hulbert, 1993; Kelly, 1995, 1998;

Woodburne, 1996), no previous studies have applied quantitative biogeographic methods

to analyze the geographic and ecological patterns of this radiation. The goal of this thesis

is to examine equid biogeography quantitatively to determine how environmental and historical variables (i.e. climatic and tectonic changes) contributed to this radiation.

Distribution patterns on both the continental and local scale are analyzed to allow

assessment of both the regional and local results of the effects of these variables. As

climate changes today, understanding how the same variables influenced the distribution

and evolution of species in the past becomes important to understanding the current

biodiversity crisis.

The radiation of the subfamily Equinae occurred during the Miocene, a time of

climatic, tectonic and environmental change (Webb et al., 1995). Temperatures rose from

the Oligocene and reached a maximum in the Miocene of appromixmately 13° C for

bottom water paleotempeartures at about 15-17 Ma (Cooke et al., 2008). Then 11

temperatures dropped dramatically as ice sheets formed over Antarctica (Zachos et al.,

2001; Rocchi et al., 2006; Lewis et al., 2007) reaching modern Antarctic Intermediate

Water temperatures at about 5.5°C (Cooke et al., 2008). The Cordilleran region on the

western margin of North America was experiencing active uplifting, creating a

rainshadow effect that caused increasing arid conditions in parts of central and western

North America (Leopold and Denton, 1987; Hulbert, 1993). This climatic change resulted in a shift of vegetation cover in parts of North America as well. In the Great Plains and southwestern regions, leafy vegetation, such as trees and shrubs, was replaced by spreading grasslands (Wolfe, 1985; Leopold and Denton, 1987; Jacobs et al., 1999). This shift in vegetation style, however, did not occur in the coastal regions of North America, where leafy vegetation persisted in a more humid climate (Webb et al., 1995; Retallack

2007).

The Equinae clade provides an example of a clade that radiated during a time of dramatic environmental change. The clade is appropriate for both phylogenetic and environmental niche based biogeographic analysis because the fossil record of its species is both abundant and well-sampled. Missing data in a biogeographic study can either represent true absence of the taxa in an area or it can be a product of under sampling.

Abundant occurrence data is important for any biogeographic analysis in order to prevent false results from absence data. In addition, there is a large volume of literature on

Equinae species regarding their phylogenetic relationships, morphological characteristics, diet, and relationship with the environment. Equinae, therefore, an excellent group of taxa 12

with which examine how changing historical and environmental conditions are related to

evolutionary processes in a biogeographic framework.

The two papers included in this thesis each examine separate but related aspects

of the biogeography of the Equinae clade. The analyses focus on different geographic

scales but both examine how environmental change affected the evolution of the clade.

The first paper examines the phylogenetic biogeography of Equinae species from four

regions of North America. This paper utilizes Lieberman-modified Brooks Parsimony

Analysis (Lieberman, 2000) to determine whether specific speciation events within the

clade are related to vicariance events, dispersal events, or both. The final output of the

study examines whether clade level patterns developed due to cyclical geological events,

such as climatic oscillations, or singular geological events, such as tectonic events.

The second paper focuses on ecological controls on species level biogeographic

patterns in the Great Plains region of North America. Individual species distributions are

analyzed in order to understand how climatic change influenced the biogeographic

patterns at the ecological level. Environmental niche modeling using a genetic algorithm

is used to predict species distribution based on environmental parameters and known

occurrence data. Species’ distributions are analyzed by size and pattern to compare

shifting climatic and environmental variables. Two primary conclusions can be drawn

from the analysis: how species ranges shifted due to climatic conditions and how this

shifting affected evolutionary patterns.

The combined results of both analyses conclude that the evolution of Equinae was driven by cyclical processes (climate change). At the regional scale, geodispersal 13 was the dominant mode of speciation. As climate changed, environmental barriers were rising and falling, leading to the radiation of the clade. At the local level, climate change resulted in habitat fragmentation evidenced by patchy distribution patterns. This resulted in niche partitioning and speciation within the Equinae clade. As climate changed, species tracked their preferred habitats. This pattern is observed at the regional and local scale as equids migrated from the Southwest to the Great Plains and then the Great Plains to the Gulf Coast. Despite habitat tracking, the decline of the Equinae clade began in the

Late Miocene. The decline was a result of loss of habitat from climatic deterioration and due to reduced speciation rates as distributions became continuous and widespread.

References

Hulbert, Jr., R.C., 1993. Taxonomic evolution in North American Neogene horses (Subfamily Equinae): the rise and fall of an adaptive radiation. Paleobiology 19 (2), 216-234.

Jacobs, B.R., Kinston, J.D., Jacobs, L.L., 1999. The origin of grass-dominated exosystems. Annals of the Missouri Botanical Garden 86 (2), 590-643.

Kelly, T.S., 1995. New Miocene horses from the Caliente Formation, Cuyama Valley Badlands, California. Natural History Museum of Los Angeles County, Contributions in Science 455, 1-33.

Kelly, T.S., 1998. New Middle Miocene equid crania from California and their implications for the phylogeny of the Equini. Natural History Museum of Los Angeles County, Contributions in Science 473, 1-43.

Leopold, E.B., Denton, M.F., 1987. Comparative age of grassland and steppe east and west of the northern Rocky Mountains. Annals of the Missouri Botanical Garden 74, 841-867.

Lewis, A.R., Marchant, D.R., Ashworth, A.C., Hemming, S.R., Machlus, M.L., 2007. Major middle Miocene global climate change: evidence from East Antarctica and the Transantarctic Mountains. Geological Society of America Bulletin 119(11), 1449-1461.

Lieberman, B.S., 2000. Paleobiogeography. Kluwer Academic/Plenum Publishers, New York, 208 pp.

MacFadden, B.J., 1992. Fossil Horses: Systematics, Paleobiology, and Evolution of the Family Equidae. Cambridge University Press, Cambridge, England, 369 pp.

MacFadden, B.J., Hulbert, Jr., R.C., 1988. Explosive speciation at the base of the adaptive radiation of Miocene grazing horses. Nature (London) 336, 466-468.

Retallack, G.J., 2007. Cenozoic paleoclimate on land in North Amirca. The Journal of Geology 115, 271-294.

Rocchi, S., Di Vincenzo, G., LeMasurier, W.E., 2006. Oligocene to Holocene erosion and glacial history in Marie Byrd Land, West Antarctica, inferred from exhumation of the Dorrel Rock intrusive complex and from volcano morphologies. Geological Society of America Bulletin 118, 991–1005.

Simpson, G.G., 1951. Horses: The Story of the Horse Family in the Modern World and through Sixty Million Years of History. Oxford University Press, Oxford, England, 247 pp.

Webb, S.D., Hulbert, Jr., R.C., Lambert, W.D., 1995. Climatic implications of large- herbivore distributions in the Miocene of North America. In: Vrba, E.S., Denton, G.H., Partridge, T.C., Burckle, L.H. (Eds.), Paleoclimate and Evolution with Emphasis on Human Origins. Yale University Press, New Haven, Connecticut, pp. 91-108.

Wolfe, J.A., 1985. Distribution of major vegetation types during the Tertiary. Geophysical Monograph 32, 357-375.

Woodburne, M.O., 1996. Reappraisal of the Cormohipparion from the Valentine Formation, Nebraska. American Museum of Novitiates 3163, 56 pp.

Zachos, J.C., Pegani, M., Stone, L., Thomas, E., Billups, K., 2001. Trends, rhythms, and aberrations in global climate 65 Ma to present. Science 292, 686-693.

CHAPTER 2: PALEOBIOGEOGRAPHY OF MIOCENE EQUINAE OF NORTH

AMERICA: A PHYLOGENETIC BIOGEOGRAPHIC ANALYSIS OF THE

RELATIVE ROLES OF CLIMATE, VICARIANCE, AND DISPERSAL

Abstract

The horse clade Equinae underwent a major radiation during the Miocene in

North America, diversifying from one species, Parahippus leonensis, to 70 species. This radiation has been linked to climatic and vegetation changes that occurred in North

America during this time. However, the relationship between climate change and speciation has not previously been studied quantitatively using phylogenetic biogeography. Distribution and age-range data were collected for all North American species within eighteen equine genera through a literature review and use of the

Paleobiology Database. Distribution data were analyzed using the Lieberman-modified

Brooks Parsimony Analysis (LBPA) to determine patterns of vicariance and geodispersal, using four constrained biogeographic regions within North America in the analysis: the

Great Plains, the Southwest, the Gulf Coast and the Southeast. Results from the LBPA indicate that speciation by dispersal was much more common in the evolution of the clade than speciation by vicariance. Patterns of distribution are congruent with geolgocial events, such as uplift of the Rocky Mountains, and climatic conditions, such as the change from a warm and moist to cool and arid climate during the Miocene. Well supported vicariance and geodispersal trees derived from the LBPA analysis are largely 17

congruent with each other, indicating that cyclical events, in particular, climate change

during the Miocene influenced the radiation of the clade.

Introduction

The coevolution of the Earth and its biota has long been studied to investigate

speciation and the process of evolution (Wallace, 1855; Valentine and Moores, 1970,

1972; Mayr,1982; Tiffney and Niklas, 1990; Lieberman, 2000 ). Depending on where and

when an organism lived, large scale Earth history events (orogenesis, continental fragmentation) or climatic change may have resulted in environmental changes which led to the divergence of populations and ultimately speciation. By analyzing the distribution of the species within a phylogenetic framework, it is possible to elucidate the roles of climatic change and/or Earth history events influencing speciation (Lieberman, 2000).

Deciphering the primary driver of speciation and subsequent evolution within a lineage

provides insight into how these taxa interacted with their environment in the past, and

importantly, may predict how they will react to environmental changes in the future.

The dramatic radiation of Equinae is often cited as a classic example of an

adaptive radiation, reflecting rapid speciation in response to environmental change (e.g.,

MacFadden and Hulbert, 1988; Hulbert, 1993). During the Early Miocene, this clade consisted of a single species, Parahippus leonensis, but by the Late Miocene had diversified into 70 named species belonging to 18 named genera (Fig. 1) (MacFadden,

1992). This diversification occurred contemporaneously with

Figure 1. Temporally calibrated cladogram of the Equinae. Phylogenetic relationships adapted from Hulbert (1993) and modified using Kelly (1995, 1998), Prado and Alberdi (1996), and Woodburne (1996). ICS temporal scale from Gradstein et al. (2004) and North American Land Mammal Ages (NALMA) from Alroy (2003). Narrow vertical lines indicate ghost lineages, wharas bold vertical lines indicate the recorded range. Stratigraphic distributions of data derived from sources in Appendix B. Taxa abbreviations: Plio.= Pliohippus, Acrit. = Acritohippus, Cal. = Callippus, Pro. = Protohippus, Neo. = Neohipparion, Pseud. = Pseudhipaprion, Hipp. = Hipparion, Nann. = Nannippus.

environmental changes resulting from climatic cooling and the spread of grasslands across North America. Whereas the general patterns, including phylogenetic relationships, associated with the Equinae diversification are well-understood, prior analyses have not utilized quantitative paleobiogeographic methods to examine the relationship between biogeographic and cladogenetic patterns in the group.

This study quantitatively assesses paleobiogeographic patterns within North

American members of the Equinae clade during their Miocene radiation using phylogenetic biogeography. The Equinae clade is an excellent candidate for a phylogenetic biogeographic study because evolutionary relationships between the species within the clade are well constrained (MacFadden, 1998; Hulbert, pers. communication

2007) (Fig. 1) and the fossil record of horses is densely sampled in North America during this interval (MacFadden, 1992). These two factors combine to create a strong evolutionary and taphonomic framework in which to examine biogeographic response to climate change. In particular, I evaluate (1) the dominant mode of speciation apparent in the clade, (2) the relationship among biogeographic areas inhabited, and (3) the relative roles of climatic versus tectonic events during the evolution of the group. Determining species ranges and distributions within a phylogenetic framework will provide additional insight into the radiation of Equinae during climate change and the subsequent extinction of the clade.

A phylogenetic biogeographic approach to studying the distribution of species can reveal patterns of speciation driving the evolution of the clade: divergence and speciation 20

(vicariance) as well as range expansion and dispersal (geodispersal). Speciation by vicariance occurs when a parent population is broken into two or more populations due to the introduction of a physical barrier such as orogenic uplift or tectonic rifting zones.

Fragmentation of the population leads to reproductive isolation and eventually the population evolves into two separate species (Mayr, 1942; Lieberman, 1997). Speciation by geodispersal occurs when a parent population expands its range as barriers fall and then becomes fragmented when the same or new barriers rise again, leading to reproductive isolation and speciation (Lieberman and Eldredge, 1996). Speciation by geodispersal, therefore, is due to cyclical processes, with the rising and falling of barriers.

It is an active mode of speciation in which the organisms have migrated, whereas

vicariance is a passive mode of speciation. During the Miocene, terrestrial clades may

have speciated due to vicariance by such processes as mountain uplift, introduction of

new waterways, or habitat fragmentation due to climate change. Since there were no cyclical tectonic events in North America during the Neogene, terrestrial clades may have

speciated by geodispersal from the fragmentation, rejoining, and shifting of habitat due to

climate change.

Phylogenetic biogeographic analysis, and in particular Lieberman-modified

Brooks Parsimony Analysis (LBPA), the methodology used herein, is effective in

interpreting the underlying factors, such as tectonic events and climate change, driving

the speciation of a clade (Lieberman, 1997). Moreover, the impact of climate change on

speciation can also be analyzed by comparing the geographic ranges of species with

changes in the climate (Stigall and Lieberman, 2006). Whereas this method has 21

previously been applied to marine invertebrates (Lieberman and Eldredge, 1996;

Lieberman, 1997; 2000; Stigall Rode and Lieberman, 2005) and fossorial reptiles

(Hembree, 2006), this represents the first application of the method to mammals.

Geologic and Paleoclimatic Framework

The position of the North American plate during the Miocene was similar to its

present geographic position. Significant tectonic activity occurred along the western

margin of the continent including uplift of the Rocky Mountains, extension resulting in

the Basin and Range province, and volcanic eruptions in the Northwest (Cole and

Armentrout, 1979; Prothero, 1998). Although the eastern portion of the continent was tectonically quiescent, this region was heavily influenced by fluctuating sea levels. For example, early in the Miocene, sea level was approximately 20 m higher than present

(Kominz et al., 1998). Low-lying parts of the continent, like Florida and the Gulf Coast

were repeatedly inundated by transgressive events (Scotese, 1998). Overall, sea level

dropped by the Late Miocene, exposing Florida and parts of the Gulf Coast (Kominz et

al., 1998).

From the Miocene into the Pliocene climate fluctuated with an overall trend

changing from warm and humid toward cool and dry (Barron, 1973; Partridge et al, 1995,

Zachos et al., 2001). Temperatures increased from the cooler Oligocene into the Miocene

and peaked at 17 Ma (Woodruff et al., 1981; Prothero, 1998). About 15 Ma, during the

Middle Miocene, ice sheets formed permanently on Antarctica, causing cooling in North

America (Zachos et al., 2001; Rocchi et al., 2006; Lewis et al., 2007). In addition, a large 22

rain shadow effect developed in the Great Plains and southwestern regions of North

America due to the uplift of the Cordilleran region including the Cascade and Sierra

Nevada Ranges (Leopold and Denton, 1987; Hulbert, 1993). Moisture levels decreased in

North America due to both the rain shadow effect (Woodruff et al., 1981; Zubakov and

Borzenkova, 1990) and global cooling (Leopold and Denton, 1987). Around 8 Ma, North

America experienced a brief warming trend and then cooled again during the Messinian

(Hemingfordian) glaciation (Prothero, 1998).

The fluctuating and changing climate created a mixture of vegetative habitats

across North America. Axelrod (1985) and Leopold and Denton (1987) suggest a subtropical mesic climate and vegetation in North America during the Early Miocene.

Savanna and grassland habitats increased throughout the Miocene due to cooling and the rain shadow effect. This transition included an increase in grasslands with lower

productivity. Isotopic evidence from mammalian tooth enamel reveals a shift from C3- based savannas to C4-based grasslands during the Miocene (Cerling, 1992; Cerling, et.

al., 1993; Wang et al., 1994). By the Pliocene, central North America was covered in a

mostly treeless prairie (Webb et al. 1995). A variety of habitats, therefore, existed in

North America during the Miocene from grasslands in the Great Plains and swamps

along the Gulf Coast to arid regions in the Southwest. This is in contrast to earlier times

in the Cenozoic when vegetative regimes were not as extreme through out North America

due to consistent temperatures and climate across the continent. Changing climate led to

fragmentation and shifting of habitats, resulting in a diverse assemblage of vegetative

regimes in each region. In each of the regions, a range of vegetative habitats existed that 23 shifted as the climate changed. These habitats supported a diverse group of browsers, grazers and mixed-feeders (Webb, 1983).

The climate change from warm and humid to cold and dry was initiated by both tectonic events, such as uplift in the Cordilleran region, and the onset of continental glaciations over Antarctica. On the timescale of this study (approximately 15 million years), however, the primary mechanism fluctuating was climate and not tectonic processes. To clarify, geological conditions of the Miocene refer to those described in this section (i.e., uplift in the Rocky Mountains and Cordilleran regions, sea level).

Climatic conditions refer to the changing climate that resulted in changing vegetations throughout North America during the Miocene.

Evolutionary Framework

The Miocene radiation of the Equinae clade was associated with significant changes in both the dentition and aspects of the locomotory apparatus (MacFadden,

1992). The basal genus Merychippus, a taxon which mesodont dentition, radiated between 18 and 15 Ma (Hemingfordian) (Hulbert, 1993). This was during the warmest period of the Miocene when vegetation consisted primarily of riparian forests, deciduous open forests, and wooded, semi-open savanna (Axelrod, 1985) that supported browsing species with mesodont dentition. The second radiation was between 15 and 12 Ma, in which the dominant taxa were hypsodont species of the tribes Hipparionini, Protohippini and Equini. Hypsodont species richness became greater than that of mesodont species

(Hulbert, 1993), with mesodont taxa becoming extinct by ~11 Ma. This taxonomic shift 24

corresponds with the first two cooling events of the Miocene at 15.3-13.5 and 12.8-12.3

Ma (Hulbert, 1993) that led to a decrease in rainfall and a shift from woodland to

grassland habitats (Axelrod, 1985). Hulbert (1993) attributed the turnover from

mesodonty to hypsodonty to the climate and vegetation changes. The subfamily’s

diversity reached a peak of 13 genera during the Clarendonian (11.5-9 Ma.) with a

mixture of mesodont and hypsodont forms (Hulbert, 1993). By the middle of the

Pliocene, however, only three Equinae genera remained, all exhibiting extreme

hypsodonty. And by the end of the Pleistocene all genera except the modern Equus had become extinct (Webb, 1984).

The evolution of taxa in response to climate during the Miocene has been well documented for equids (e.g., Shotwell, 1961; Webb, 1977, 1983; Stebbins, 1981; Janis,

1984, 1989; Thomasson and Voorhies, 1990). Horses have been cited as a classic example of evolution in the fossil record (ex., Marsh, 1879; Matthew, 1926; Stirton,

1940; MacFadden, 1992) and these studies demonstrate a clear link between climate change and evolution (e.g., Simpson, 1951). Previous biogeographic studies of horses have ranged from analyses of local patterns, such as in the Great Basin (e.g., Shotwell,

1961), to global surveys, hypothesizing that horses originated in North America and later dispersed to Europe and Asia (e.g., Lindsay et al., 1979; Lindsay et. al., 1984;

MacFadden, 1992; Opdyke, 1995). Whereas these studies provide an excellent framework for examining the correlation between the diversification of the Equinae and

environmental change, none has analyzed spatial distributions in a phylogenetic

framework or applied quantitative biogeographic methods. 25

The major radiation of the Equinae clade during the Miocene has been attributed

to the spread of grasslands. The classic story, however, has been augmented in recent

years. For example, original hypotheses of orthogenetic evolution of the clade (e.g.,

Simpson, 1951), have been dismissed with the discovery of the tridactyl Nannipus,

Neohipparion and Cormohipparion living in the Late Miocene with the “advanced”

monodactlys (MacFadden, 1984, 1998). In addition, while the level of hypsodonty is often considered a proxy for browsing vs. grazing lifestyles (Kowalevsky, 1874;

Matthew, 1926; Simpson, 1951, Stebbins, 1981), other studies have demonstrated that the

dentition of a horse species is not always conclusive evidence for the type of vegetation

in their diet (Stirton, 1947; Fortelius, 1985; Janis, 1988) and, therefore, cannot be used as

the sole proxy for vegetation types. Stromberg (2006) advised against using tooth morphology alone to reconstruct habitat change due to inconclusive evidence regarding whether hypsodonty was an adaptive characteristic. The adaptation and speciation of this clade is more complex than originally thought. It is understood that environmental changes caused by climate fluctuations and vegetation change influenced the radiation of the clade (e.g., Hulbert, 1993; Webb, et al., 1995). Here I assess this claim and elucidate the details of the pattern by examining and statistically analyzing distributional data to better understand environmental influences on equine speciation.

Materials and Methods

Taxa and geographic regions

The phylogenetic hypothesis of equine relationships used in this study is adopted primarily from Hulbert (1993) and amended with relationships presented in Kelly (1995,

1998), Prado et al. (1996), and Woodburne (1996) (Fig. 1).

Distribution data for included taxa were compiled from the primary literature, the

Paleobiology Database (www.paleodb.org), and the National Museum of Natural History

(NMNH). A complete list of referenced studies is included in Appendix B.

To assess biogeographic patterns North America was divided into four areas of

endemism (Fig. 2): the Southeast, the Gulf Coast, the Great Plains, and the Southwest.

Areas of endemism were defined based on previous biogeographic divisions of the clade

(Webb and Hulbert, 1986; Hulbert, 1987; Hulbert and MacFadden, 1991; Webb et al.,

1995) and the presence of natural barriers (either climatic or geographic) on the North

American plate during the Miocene. Species distribution data used in this study are

congruent with the four areas of endemism used in previous studies. Additional areas of

endemism may have existed, but the fossil record of those regions is too sparse to include

in this analysis. Fossil Equinae are known from the Northwestern region of North

America (e.g. Oregon, Idaho) and the Northeastern region (North Carolina and

Delaware). The remains of only four species were located in the Northwest and only two

species in the Northeast. When areas of endemism with only a few species are

incorporated into phylogenetic biogeographic analyses, insufficient character data are

present in the data matrix for these areas, and the optimization procedure cannot assess 27

correctly their placement in the parsimony analysis. These areas will simply place out at

the base of the reconstructed area cladograms, thereby providing no information

Figure 2. Endemic geographic areas of the subfamily Equinae in North America analyzed in this study. The Southeast area includes sites in Florida. The Gulf Coast area stretches along the coast from Florida to the Mexican border. The Great Plains area begins approximately 400 km north of the Gulf Coast and stretches on the eastern side of the Rocky Mountains through Texas, New Mexico, Oklahoma, Kansas, Nebraska, Colorado, Wyoming, North and South Dakota, and Montana. The Southwest region included locations west of the Rocky Mountains in New Mexico, Arizona, California, Nevada, and Utah. The grey region represents the Rocky Mountain range during the Miocene. 28

(Lieberman, 2000; Stigall Rode and Lieberman, 2005). Consequently, I excluded these

areas from this analysis due to methodological limitations.

Analytical Biogeographic Method

Lieberman-modified Brooks Parsimony Analysis (LBPA) as described in

Lieberman and Eldredge (1996) and Lieberman (2000) is the phylogenetic biogeographic method employed in this study. This method was selected because it is designed to resolve both vicariance and geodispersal patterns as well as assess the relative impact of

cyclic versus singular events on the biogeographic history of a clade. Whereas other

analytical methods for phylogenetic biogeography exist, they either cannot detect

geodispersal or require simultaneous analysis of multiple clades (see discussion in Stigall,

2008). LPBA has been successfully used to resolve biogeographic patterns in the fossil

record during intervals in which the primary driver of biogeographic patterns included

both climatic oscillations (e.g., Lieberman and Eldredge, 1996; Stigall Rode and

Lieberman, 2005) and tectonic events (Lieberman, 1997; Hembree, 2006).

The methodology of this analysis is explained in detail in Lieberman (2000) but a

brief discussion is presented here. The first step in the analysis is to convert the

phylogenetic tree of Equinae into an area cladogram by replacing taxon names with the

areas of endemism in which each species occurred. Biogeographic states for the internal

nodes are optimized using Fitch Parsimony (Fitch, 1971). The cladogram based on

Hulbert (1993), Kelly (1995, 1998) and Woodburne (1996) is shown as an area

cladogram with optimized nodes in Figure 3. Two matrices, a vicariance matrix and a 29

geodispersal matrix, are coded for parsimony analysis from the area cladogram. In both

matrices, areas of endemism are treated as taxa, whereas individual nodes and branches

of the area cladogram are coded as characters (see Appendix 1). The two matrices are

then evaluated separately using parsimony and provide different information about the relationship between the areas of endemism.

The vicariance matrix is used to ascertain vicariance patterns within the area cladogram. In coding the matrix, an ancestral area is added for character polarization and is coded 0 for all character states. The biogeographic state of each node or terminus is coded as 0 when it is absent from an area and 1 if present. If a node represents a derived speciation event due to range contraction (vicariance) it is coded 2, which is treated as an ordered character state. The matrix was analyzed with PAUP 4.0b10 (Swofford, 2002) under an exhaustive search to determine the most parsimonious tree. The vicariance tree indicates the relative timing of separation for the four areas. Areas that group most closely on the tree were separated most recently by a barrier, such as orogenic uplift or habitat fragmentation. In contrast, areas more distally related on the tree were separated by a barrier more ancestrally.

The second analysis examines geodispersal events across the clade. A matrix was coded with geodispersal events, similarly to the matrix for vicariance. Descendant taxa that occupy novel or additional areas of endemism are coded as a derived presence (2).

The matrix was analyzed with PAUP 4.0b10 in the same way as for the vicariance matrix. The geodispersal tree indicates the relative timing that dispersal occurred between 30

areas. It demonstrates which areas were most recently connected, thereby allowing

dispersal between them, and which ones were connected more ancestrally.

Comparison of the two tree topologies indicates whether deterministic events, such as tectonic events, are driving the evolution of a clade or whether cyclical events, such as oscillatory climate change, are affecting its evolution. Congruent tree topologies illustrate that the order in which barriers arose is the same order in which they fell.

Consequently, if the vicariance and geodispersal trees exhibit congruent topologies, then cyclical events have influenced the resulting biogeographic patterns. Conversely, if the trees are incongruent, then geodispersal and vicariance events did not occur between regions in a cyclical pattern (or at least are not cyclical on a timescale effecting speciation). Instead, singular events influenced the evolution of the clade (Lieberman and

Eldredge, 1996; Lieberman, 1997).

Results

Speciation Patterns

Analysis of the biogeographic optimization provides the opportunity to assess mode of speciation. In cladogenetic events where the descendant species occupies only a subset of a larger ancestral range, speciation is interpreted to occur by vicariance.

Conversely, when descendant species colonize areas additional to or distinct from the ancestral species, speciation is interpreted to result from dispersal. Speciation by dispersal is the primary mode of speciation across this clade (Fig. 3). Of cladogenetic 31

events where speciation mode could be assessed, there were 47 speciation events by

dispersal and only 9 speciation events by vicariance.

The overall pattern of biogeographic evolution in this clade can also be assessed

from the area cladogram (Fig. 3). Parahippus leonensis and “Merychippus” gunteri, the ancestral species, lived primarily along the Gulf Coast and Southeast. However, the

Equinae clade began its radiation further inland in the Great Plains. The three tribes of the

Equinae clade (Equini, Protohippini and Hipparionini) diversified in three different areas of North America. The tribe Equini separated from the other two tribes first and diversified in the Southwest. Then the tribe Protohippini divided from the tribe

Hipparionini. Ancestors of the tribe Protohippini continued to diversify in the Great

Plains as well as along the Gulf Coast. The tribe Hipparionini continued to speciate in the

Great Plains (Fig. 3). Later, however, species in each tribe dispersed from their ancestral regions into other areas.

Biogeographic Area Analysis

The vicariance analysis produced a single most parsimonious tree (Fig. 4A). The consistency index (0.821), a measure of homoplasy, is statistically significant (p < 0.05) and indicates strong tree support (Sanderson and Donoghue, 1989; Klassen et al., 1991).

The g1 statistic (g1 = - 0.214) indicates the tree length distribution is skewed to the left,

and shows a significant phylogenetic signal at the level of p < 0.05 (Hillis and

Huelsenbeck, 1992). The Great Plains and Southwest are most closely related indicating

that a vicariance event created a barrier between them most recently. Ancestral to this 32

x acter number in the data matri e 1. Areas of endemism from Figure 2 – Southwest. Circles indicate char – Southwest. Circles indicate ade based on phylogenetic topology in Figur entified as: V = vicariacne event, or D dispersal event. labeled as: 1 – Southeast, 2 Gulf Coast, 3 Great Plains, 4 (Appendix A). Speciation at nodes id Figure 3. Area cladogram of the Equinae cl 33

event, the Southeast was separated from the Great Plains and Southwest by a vicariant

event. The Gulf Coast was separated from all three of the areas ancestrally.

The geodispersal analysis also produced a single most parsimonious tree (Fig.

4B). The consistency index (0.805) and g1 (g1 = 0.148) are statistically different from

random (p < 0.05) (Sanderson and Donoghue, 1989; Klassen et al., 1991; Hillis and

Huelsenbeck, 1992), indicating strong tree support. The Gulf Coast and Southeast are

closely related as well as the Great Plains and Southwest. Dispersal between these

subregions occurred ancestrally.

The topologies of the vicariance and geodispersal trees are largely congruent (Fig.

4). The primary difference between them is the relative relationship of the Southeast. In

the geodispersal tree the Southeast is most closely related to the Gulf Coast; whereas in

the vicariance tree the Southeast is more closely related to the Great Plains/Southwest

than to the Gulf Coast. The geodispersal tree represents a clear division between the

Great Plains/Southwest and the Gulf Coast/Southeast whereas the vicariance tree represents a relative progression of separation between all four regions. The Great Plains and Southwest, however, have a strong relationship on both trees.

Discussion

Distributional Patterns

The dominant mode of speciation within the Equinae clade is dispersal (Fig. 3)

This is consistent with the migratory life habits of horses. The ancestral Parahippus leonensis did not breed seasonally or migrate, most likely because its habitat was 34

(2) Dispersal tree; Brooks Parsimony Analysis of statistic is -0.214. 1 ved from Lieberman-modified ved from Lieberman-modified statistic is 0.148. 1 181 steps, consistency index is 0.821, and g tency index is 0.805, and the g Appendix A. (1) Vicariance tree; length is length is 231 steps, consis Figure 4. Vicariance and geodispersal area cladograms deri 35 consistent year round (Hulbert, 1984). Hyposodont horses, however, did migrate to exploit food resources and did breed in a seasonal environment (Van Valen, 1964;

Voorhies, 1969). Studies of the global biogeographic distribution of the clade apply the mode of dispersal to explain their migration from North America to Europe and Asia through the Neartic (Lindsay et. al., 1984; Opdyke, 1995). The few vicariant events in

Figure 3 are either related to the isolation of the Southwest region or the climatic deviation between the Gulf Coast and Great Plains areas. These events likely resulted from tectonic uplift in the west and differences in vegetation types in the east, respectively, and will be discussed in more detail below.

The area cladogram and distribution of Equinae is consistent with Miocene tectonics in North America. For example, species are distributed in areas of the Florida

Platform that were above sea level during the Miocene (Appendix B). Species are also distributed in areas of central New Mexico where the Rocky Mountain range had a narrower expanse during the Neogene compared to northern parts of its range (Trimble,

1980). The narrower expanse provided an area of passage between the Southwest and

Great Plains regions in New Mexico during the Miocene. Conversely, no taxa were recorded from areas in the northern Rocky Mountains where the mountains had a wider expanse (Appendix B).

The ancestral biogeographic states and the topology of the area cladogram show patterns of speciation that are consistent with the climate and distribution of vegetation during the Miocene. Ancestral taxa, Parahippus leonensis and Merychippus gunteri, inhabited the Gulf Coast regions (Fig. 3). However, none of the basal equid nodes 36

diversified there. The consistently moist conditions of the Gulf Coast provided a stable

habitat that may have reduced opportunities for allopatric differentiation and inhibited the

speciation of equid ancestors in the area. The Protohippini was the only tribe to diversify

in the Gulf Coast area whereas the tribes Hipparionini and Equini speciated in the

changing and fragmented habitats of other regions in North America (Fig. 3).

Changing climatic conditions led to altered vegetation regimes in North America,

but this was affected differently in the areas of endemism considered herein. The Gulf

Coast and Southeast areas continued to include browsing habitats after the Great Plains and Southwest regions transitioned into arid grasslands (Wolfe, 1985). The Gulf Coast region became a refuge for taxa that became extinct in the Great Plains (Webb et al.,

1995). Species such as Cormohipparion emsliei, Pseudhipparion simpsoni and

Nannippus aztecus, tridactyls belonging to the tribe Hipparionini and adapted for browsing and selective grazing, survived in the Gulf Coastal regions long after becoming extinct in the Great Plains and Southwest (Webb and Hulbert, 1986; Webb et al., 1995).

Ancestral members of the tribe Hipparionini were distributed in the Great Plains (Fig. 3).

Several of the terminal taxa, however, occupied the Gulf Coast and Southeast areas indicating a movement to the warmer areas. The area cladogram (Fig. 3) expresses the refuge characteristic of the moist coastal regions.

The general distribution of taxa throughout North America expressed in the area cladogram is closely related to the morphology of the Equinae species (Fig. 3). Although it has been demonstrated that monodactyl and tridactyl species were sympatric in North

America (MacFadden, 1992), limb morphology was found to vary between different 37 areas and, consequently, vegetation types (Fig. 3). The tribe Equini that contains the dominantly monodactyl genera Astrohippus, Dinohippus, and Equus diversified in the

Great Plains area (Fig. 3). Tridactyl genera of the tribe Hipparionini (e.g.

Cormohipparion and Nannipus) diversified in the Great Plains but were the more common taxa in the Southeast. The tribe Protohippini contained tridactyl genera that diversified along the Gulf Coast. According to Renders (1984), tridactyl limb morphology provided more traction in muddy substrates. Muddy substrates were more abundant in warm humid areas of the Gulf Coast regions as opposed to the arid conditions of the Great Plains (Retallack, 2007). Although monodactyl and tridactyl species lived in the same endemic areas, they did occupy different ecological niches within those regions (MacFadden, 1992). Shotwell (1961) determined that the tridactyl horses preferred a mosaic of savanna and forest habitats of the northern Great Basin. As the grasslands became more widespread in the Great Basin, monodactyl horses became dominant (Shotwell, 1961).

Vicariance Patterns

The vicariance tree indicates the relative order in which areas of endemism were separated by vicariance events. The relative order presented in Figure 4A is congruent with the interpreted geologic and climatic conditions of the Miocene in North America.

The Southwest and Great Plains were separated most recently by a barrier (Fig. 4A). This separation is related to the final phase of uplift in the Rocky Mountains, which began in the Miocene following a tectonic quiescent period from the Cretaceous through the 38

Oligocene (Effinger, 1934; Frazier and Schwimmer, 1987). This slow and gradual uplift during the late Cenozoic persisted into the Pliocene. During the Miocene, the Southwest and Great Plains had different vegetation due to the uplift (Leopold and Denton, 1987). A rain shadow resulted in drier conditions east of the Rocky Mountains, thereby creating a vegetative difference between the two regions. East of the Rocky Mountains vegetation consisted of deciduous open forests ad prairie. To the west of the mountain range, deciduous hardwood forests and swamps dominated the vegetation (Leopold and Denton,

1987). Although grasses were present west of the Rocky Mountains in the Early

Miocene, their abundance was not significant. Leopold and Denton (1987) attribute the difference in abundance to the inability of grasslands to spread across the mountainous barrier and the montane conifer forest that occupied the mountainous terrain. Grasslands became sporadically abundant west of the Rocky Mountains during the Blancan

(Pliocene) when they spread from the northern Great Plains as they adapted to a summer- dry climate from a summer-wet climate.

The Southeast branches from the tree next (Fig. 4A). Its position here on the vicariance tree is probably a result of pre-Miocene sea level fluctuations. As the amount of exposed land of the Florida Platform varied, populations were divided. Leading into the Miocene, the Gulf Trough separated Florida from the continent (Randazzo and Jones,

1997). Through the Neogene, sediment shed from the North America continent filled in the trough and made Florida contiguous with the North American continent, thereby allowing dispersal of the ancestral species. The early vicariant events, however, are represented by the ancestral location of the Southeast on the vicariance tree. 39

The Gulf Coast region branches off ancestrally on the vicariance tree because there were no tectonic barriers between it and the Great Plains/Southwest areas (Fig. 4A).

It acted as a passage way between the Southwest and Great Plains, and the Southeast

(Fig. 4A). There were no physical barriers in the Gulf Coast region restricting dispersal - the Mississippi River had not developed to its current size yet (Scotese, 1998).

During the Early Miocene vegetation supported by a warm and humid climate was present in all four areas of endemism (Axelrod, 1985; Wolfe, 1985). A relatively quiescent tectonic setting combined with a stable flora allowed dispersal between the northern (Great Plains) and coastal areas (Gulf Coast and Southeast) by early members of the clade. These areas do not form a polytomy, however, because a climatic and vegetative difference developed between the northern and coastal areas during the mid- late Miocene. Although Axelrod (1985) describes the environment of the entire Great

Plains region during the Miocene as wooded grasslands with semi-open grassy forests and patchy grasslands, Retallack (2007) discusses a moisture gradient in the Great Plains from Montana to Nebraska and Kansas. Paleosols from Montana during the Miocene have weak pedogenic structure, low clay content, limited chemical weathering, and shallow calcic horizons indicating an arid environment (Retallack, 2007). Such paleosols represent aridic conditions from the rain shadow caused by the uplift in the Cordilleran region. Paleosols developed in Nebraska and Kansas during the Miocene exhibit fewer calcareous nodules and a higher clay content indicative of higher levels of precipitation

(Retallack, 1983, 1997). Paleosols in Oregon from the Miocene also have greater clay content and fewer calcareous nodules. Retallack (2007) interpreted that the difference in 40

paleosols among these regions is due to the proximity of Nebraska, Kansas and Oregon to

the maritime air masses from the Gulf and Pacific Coasts early in the Cenozoic.

The relative separation of the endemic areas is consistent with the tectonic and

climatic history of the North American continent during the Miocene. Vicariance events such as uplift in the western United States, isolation of Florida, and vegetational gradients have influenced the evolution of the Equinae clade.

Geodispersal Patterns

The geodispersal tree indicates the relative time in which dispersal occurred between the endemic areas. Relationships within the geodispersal tree are congruent with the tectonic and climatic events of the Miocene as well. The close association between the Great Plains and Southwest on the geodispersal tree indicates that species dispersed several times between these two regions (Fig. 4B). As discussed previously, a corridor

existed through the Rocky Mountains during the Miocene that allowed dispersal across

the southern part of the mountain range (Trimble, 1980). Forty-three percent of the

species in the Great Plains also lived in the Southwest compared to the 24% that also

lived in the Gulf Coast area. Although both the Southwest and Gulf Coast are proximal to

the Great Plains region, dispersal occurred more frequently between the Great Plains and

Southwest than with the Gulf Coast. A physical barrier (i.e., Rocky Mountains) separated

the Great Plains and Southwest (Cole and Armentrout, 1979; Trimble, 1980), whereas a

climatic barrier separated the Great Plains and Gulf Coast (Retallack, 2007). Based on the 41 available data, the climatic barrier appears to be more influential than the physical barrier.

The close relationship between the Gulf Coast and Southeast is intuitive (Fig. 4B).

These two areas were not divided by physical barriers and shared similar climates and vegetation (Wolfe, 1985) allowing migration and dispersal between them. Florida connected to the mainland continent during the Miocene when the Gulf Trough filled in with sediment shed from the Appalachian Mountains, allowing dispersal with and from the Gulf Coast (Randazzo and Jones, 1997).

Consistent vegetation in the Gulf Coast and Southeast regions may have inhibited allopatric speciation. Ancestral species that occupied the coastal regions did not speciate as frequently as species that migrated to the fragmented habitats of the cooler and drier

Great Plains and Southwest regions.

The Gulf Coast and Southeast areas are separated from the Great Plains and

Southwest by a climatic gradient (sensu Retallack, 2007) as discussed above. Dispersal between all four regions most likely occurred before the global climate began to cool and vegetation shifted from woodland to grassland in the Great Plains. During the Middle

Miocene, when distinct climatic regimes were in place (Wolfe, 1985), separating the four regions, dispersal was rare, occurring only for species tracking a browsing habitat and seeking refuge from the Great Plains in the moist, woodland coastal regions. The divergence of the four regions located ancestrally on the geodispersal tree supports the early dispersal among the areas and restricted dispersal later (Fig. 4B).

Comparison and Synthesis

The vicariance and geodispersal trees are largely congruent with one another. The

primary difference between the two trees is the location of the Southeast region. On the geodispersal tree, the Southeast is more closely related to the Gulf Coast than it is in the vicariance tree (Fig. 4). The Gulf Coast and Southeast had similar climatic regimes and woodland vegetation allowing almost continuous dispersal between them whereas the western areas (Great Plains and Southwest) had more arid climates (Axelrod, 1985;

Wolfe, 1985; Thomasson et al., 1990; Retallack, 2007) restricting dispersal to and from the coastal areas (Webb et. al., 1995). The location of the Southeast on the vicariance tree separates it from the Gulf Coast (Fig. 4). This separation is a result of pre-Miocene fluctuations in sea level and the presence of the Gulf Trough possibly causing vicariant speciation between the Southeast and other regions before the Miocene. Dispersal occurred during the Miocene when the Gulf Trough was filled in with sediment and

Florida was continuous with the mainland. This is represented by the location of the

Southeast on the geodispersal tree. The location of the Southeast on both trees is consistent with geological data and together they give an accurate representation of

Southeast’s relationship with the other three areas.

The congruency between the trees indicates cyclical events (i.e., rise and fall of

barriers) were the most significant factors driving the speciation and biogeographic evolution of the Equinae during the Miocene. Cyclical events that cause speciation on the time scale of this study are climatic change. Fluctuating climatic conditions resulting from global cooling and a rain shadow effect from the Cordilleran region created a 43 mixture of habitats in North America during the Miocene (Hulbert, 1993; Webb et. al.,

1995). A variety of habitats that resulted from these climatic changes, supported a large diversity of Equinae species that were grazers, mixed feeders, and browsers (Webb et al.,

1995).

Conclusions

Speciation of the Equinae clade was primarily driven by dispersal with a few episodes of vicariance. Speciation by geodispersal was a result of biogeographic shifts in response to environmental alteration caused by climate change. In North America during the Neogene, the fluctuating climate resulted in a variety of fragmented habitats as woodlands slowly shifted to open grasslands. The variety of habitats likely led to the diversity of the clade. Although this has been documented in previous studies (Hulbert,

1993; Webb et al., 1995), it is quantitatively presented here for the first time.

The decline in diversity of the clade during the Pliocene has been attributed to climate change as well (Hulbert, 1993). Loss of woodland habitat from climate change may have resulted in the demise of several browsing species during early stages of global cooling (Webb et al., 1995). The first major extinction interval within the clade, effecting hypsodont horses, occurred during the driest time of the Neogene and the second occurred during a return to moist conditions similar to those seen in the Clarendonian

(Axelrod, 1985; Leopold and Denton, 1987, Hulbert, 1993). During the second extinction interval, species exhibiting extreme hypsodonty were affected (Hulbert, 1993). A drop in diversity has also been attributed to increasing grasslands with lower productivity

(MacFadden, 1998) due to a shift from C3-based savannas to C4-based grasslands 44

(Cerling, 1992; Cerling, et. al., 1993; Wang et.al., 1994). In addition, as grasslands

spread, vegetation became more consistent and may have led to a decline in opportunites

for allopatric speciation.

The LPBA analysis presented here on a mammalian fauna from the Neogene is

consistent with previous studies of Equinae evolution and North American geology.

Phylogenetic biogeographic studies can be used on terrestrial taxa that have a well constrained phylogeny and abundant fossil record. Such studies may provide additional insight into the mechanisms driving the evolution of a clade with respect to the climate and geology of the distributional area. Dispersal and migration patterns can be more accurately reconstructed with such statistical methods as LBPA than with qualitative analysis. 45

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CHAPTER 3: DISTRIBUTION OF FOSSIL HORSES IN THE GREAT PLAINS

DURING THE MIOCENE AND PLIOCENE: AN ECOLOGICAL NICHE MODELING

APPROACH

Abstract

Geographic distributions of Miocene species in the Equinae clade are predicted using ecological niche modeling (ENM). Species inhabiting the Great Plains region of

North America are examined as a case study area. The Equinae underwent a dramatic radiation as climate changed from warm and humid in the middle Miocene to cooler and more arid conditions during the late Miocene. Here I analyze the predicted distribution of individual species in relation to this climate change through ENM using the GARP

(Genetic Algorithm using Rule-set Prediction) modeling system. This method predicts the geographic extent of a species’ fundamental niche based on environmental variables coupled with known species occurrence points and provides a means to quantify a species’ geographic range. Specifically, distributional patterns, habitat tracking, and species survival are examined in two time slices that span from the Mid-Miocene

(Barstovian) Climatic Optimum into the early Pliocene (Blancan). Patchy distributions are more common in the middle Miocene when speciation rates are high. During the late

Miocene, when speciation rates are lower, continuous ranges are more common. Equid species track their preferred habitat within the Great Plains region as well as regionally throughout North America. Species with larger predicted ranges survive during the initial cooling event but as climate continues to deteriorate in the late Miocene, range size is 53 irrelevant to survival and extinction rates increase. This is the first use of ENM and

GARP in the continental fossil record.

Introduction

The Equinae clade underwent a major radiation during the Miocene from one species, Parahippus leonensis, to 70 species, reaching its highest diversity during the

Middle Miocene (Clarendonian) with 13 genera (MacFadden, 1992; Hulbert, 1993). The diversification of Equinae contains a variety of dental and muzzle morphologies, as well as a diverse range of body sizes and limb proportions (MacFadden, 1992). MacFadden

(1992) and Webb et al. (1995) connect the morphological diversity to niche partitioning due to overlapping ranges. The radiation of this clade occurred in two pulses which have been attributed as adaptive responses to climate and vegetation change during the

Miocene (MacFadden and Hulbert, 1988; Hulbert, 1993). The first radiation pulse occurred at approximately 18 Ma among the basal members of the clade. The second and larger radiation occurred between 15 and 12 Ma with the emergence of hypsodonty in equids (Hulbert, 1993). This event coincides with the first major cooling event of the

Miocene (Zachos et al., 2001). Associated vegetation changes during the Miocene have been documented by paleoflora studies and stable isotope analyses of tooth enamel and paleosols (for review, see Jacobs et al., 1999). As the climate changed during the

Miocene, the vegetation shifted from predominantly forest to a mosaic of woodland savanna and riparian forests that supported browsing, grazing and mixed feeding horses

(Webb, 1983). This diversity peak, however, did not last. Equid diversity began to 54

decline during the late Miocene, and by the middle of the Pliocene only three genera were

extant (Webb, 1984). Competition with other grazers (e.g., artiodactyls, rodents) was previously inferred to have caused the decline of the clade (Simpson, 1953; Stanley,

1974; Webb, 1969, 1984), but now it is attributed to the continuing climatic deterioration

(MacFadden, 1992; Webb et al., 1995).

Although the diversification of the Equinae has been hypothesized to have resulted from climate change, induced habitat fragmentation, and ecological

specialization, the changing distribution of individual species has not been quantitatively

mapped or analyzed previously. Most paleobiogeographic studies of equids have focused

on large scale patterns, such as migration patterns from North America to the Old World

(e.g., MacFadden 1992). Other paleobiogeographic studies have grouped equids with

other Miocene mammalian clades to demonstrate general patterns, such as retreat to the

Gulf Coast region when the climate became cool and arid in northern areas of North

America during the late Miocene (e.g., Webb 1987; Webb et al., 1995). A more focused

study examining the distribution of individual Equinae species can provide a framework

in which to analyze habitat fragmentation and speciation. Since the radiation is

hypothesized to have resulted from climate change, an integrated assessment of the

ecology and biogeography is necessary to fully understand evolutionary patterns in the

clade. Shotwell (1961) recognized this in his study on the biogeography of horses in the

northern Great Basin. Shotwell (1961) observed a change in species composition that

coincided with vegetational change and concluded that the shift in the species resulted

from immigration of equid species native to other regions that were adapted to the new 55

vegetative regime into the Great Basin . However, there have been several advances in

the phylogenetic relationships of the clade and their morphologies since Shotwell’s

(1961) study which provides a more robust framework for new analyses. Furthermore,

numerous recent studies have investigated the environmental and climatic conditions of

the Great Plains during the Miocene. These studies include analyses of vegetation type

(eg. Fox & Koch, 2003; Strömberg, 2004; Thomasson, 2005), paleosol composition (eg.

Retallack, 1997,2007), and climate proxies (eg. Woodruff et al., 1981; Zachos et al.,

2001) that provide a rich source of environmental information previously unavailable for

equinid biogeographic analyses. Here I reconstruct the geographic ranges for individual

species of Miocene horses based on environmental variables to assess how changing

climate and shifting habitats affected evolutionary patterns in the Equinae.

In order to study the distribution of horses on a fine geographic scale, I employ

ecological niche modeling (ENM). A species ecological niche is defined as the set of

environmental tolerances and limits in multidimensional space that defines where a

species is potentially able to maintain populations (Grinnell, 1917; Hutchinson, 1957).

This is also known as a species fundamental niche because it contains all areas in which a species could potentially live based on the fundamental parameters needed by the species to survive. Species, however, do not fill their entire fundamental niche. Biotic intereactions result in a restricted or smaller niche called a species realized niche

(Lomolino et al., 2006). Modeling a species realized niche unfortunately is not possible from the paleontological recored. Determining the ecological or fundamental niche of a taxon, however is possible and is essential in determining its potential distribution 56

(Peterson, 2001). Ecological niche modeling uses a set of environmental variables to estimate the distribution of a species based on the set of environmental conditions of locations where a species is known to occur. The fossil record of equids is densely- sampled and abundant locality information provides a robust record of where each species lived in North America (MacFadden, 1992). Direct mapping of species ranges from known occurrence points may underestimate a species’ actual geographic range due to the inherent biases of the paleontological record (Kidwell and Flessa, 1996; Stigall

Rode, 2005). More accurate ranges can be constructed by using ENM to model species ranges based on known occurrence points and environmental parameters from the sedimentary record. Ecological niche modeling is widely employed in modern biological studies to predict the distribution of species for conservation purposes (e.g., Peterson et al., 2002; Wiley et al., 2003; Nunes et al., 2007). There are several niche modeling programs available (e.g. BIOCLIM, GARP), and all are successful in predicting the geographic range of taxa (Peterson, 2001). This study employs the GARP (Genetic

Algorithm using Rule-set Prediction) modeling system developed by R. Scachetti-Pereira

(www.lifemapper.org/desktopgarp). GARP is a learning-based analytical package that predicts the fundamental niche of a species using environmental coverage data in concert with a set of known species occurrence points (Stockwell and Peters, 1999). GARP has been successfully employed with numerous modern mammalian studies investigating ecological and environmental questions (e.g. Lim et al., 2002; Illoldi-Rangel et al., 2004).

It has also been successfully employed in the fossil record of marine invertebrates (Stigall 57

Rode and Lieberman, 2005). This study represents the first application of ENM and

GARP, however, to fossil vertebrates.

In this study I examine the distributional patterns of individual species to better

understand the rise and fall of the Equinae in relation to environmental and climatic

change. Ecological niches are modeled and geographic ranges predicted in order to study

how species’ distributions shifted through time as a result of climatic and vegetative

changes. Specifically, I will test if habitat fragmentation led to the diversification of the clade and if distributional patterns and range size affected the survivorship of individual species.

Methods

Geographic and Stratigraphic Intervals

Geographic Extent

The distributions of species belonging to the Equinae clade were predicted for two

successive time slices during the Miocene and Early Pliocene in the Great Plains region

of North America (Table 1). The study area incorporated regions of the High Plains, as

defined by Trimble (1980), which includes northern Texas, western Oklahoma, western

Kansas, Nebraska, eastern Colorado, southeastern Wyoming, and southern South Dakota

(Fig. 5). Although equid species inhabited regions of North America outside the study

area, the Great Plains region was chosen for the focus of this study due to the abundant

amount of published data on both the distribution of equid fossil material and the

environmental setting of the region during the Miocene and Pliocene. To facilitate 58 analysis of environmental data, the study region was divided into 1° grid boxes (Fig. 5), which is standard procedure for GARP analyses because modern environmental data is typically presented in this format (e.g., Stockwell and Peterson, 2002). Environmental parameter data was collected for as many one degree grid boxes as possible from literature sources (Table 2). If a grid box had more than one data point for an environmental parameter, the average value of all data points representing the parameter was reported for the grid box.

Table 1.

Species modeled in the middle (middle Miocene) and late (late Miocene to early Pliocene) time slices.

Middle Time Slice Late Time Slice Calippus martini Astrohippus ansae Calippus placidus Astrohippus stockii Calippus regulus Cormohipparion occidentale Cormohipparion occidentale Dinohippus interpolatus Cormohipparion quinni Dinohippus leidyanus Hipparion tehonense Equus simplicidens Merychippus coloradensis Nannipus aztecus Merychippus insignis Nannipus lenticularis Merychippus republicanus Nannipus peninsulatus Neohipparion affine Neohipparion eurystyle Neohipparion trampasense Neohipparion leptode Pliohippus mirabilis Pliohippus nobilis Pliohippus pernix Protohippus gidleyi Protohippus perditus Protohippus supremus Pseudhipparion gratum Pseudhipparion hessei Pseudhipparion retrusum

Table 2.

Environmental data references by variable.

† * Percent C4 vegetation (stable isotope data based on tooth enamel or paleosols ) Fox and Fisher, 2004† Fox and Koch, 2003* Passey et al., 2002† Wang et al., 1994† Clouthier, 1994†

Mean Annual Precipitation Damuth et al., 2002 Retallack, 2007 Retallack, unpublished data

Mollic Epipedon Retallack, 1997 Retallack, unpublished data

Vegetation Axelrod, 1985 Gabel et al., 1998 MacGinitie, 1962 Strömberg, 2004 Thomasson, 1980 Thomasson, 1983 Thomasson, 1990 Thomasson, 1991 Thomasson, 2005 Wheeler, 1977

Faunal Assemblages Markwick, 2007

Figure 5. A) Study area with 1° x 1° grid boxes overlain. B-C) Distribution of environmental data (red circles) and species occurrence data (blue triangles) for the middle time slice (B) and late time slice (C). Base map shows paleoelevation in meters, modified from Markwick (2007). 61

Climatic, Temporal and Stratigraphic Framework

Data was collected for three time slices in order to analyze the distribution of

species through the climatic changes of the Miocene and Pliocene (only two time slices

were used in the final analysis). The time slices (Table 1; Fig. 1) were determined based

on reversals and slope of the temperature in the climate curve of Zachos et al. (2001),

which is the Cenozoic climate curve most widely employed in the literature. This climate

curve is a compilation of global deep-sea oxygen and carbon isotope records of benthic

foraminifera from over 40 Deep Sea Drilling Project and Ocean Drilling Program sites

culled from the literature.

The first time slice spans 8.5 million years from the Arikareean through the early

Barstovian. Temperatures rose about 2°C during this interval until the Mid-Miocene

Climatic Optimum was reached at approximately 17-18 Ma (Zachos et al., 2001).

Temperature estimates from stable oxygen isotopes of benthic foraminifera in the

Tasman Sea indicate a peak at about 13°C during this interval (Cooke et al., 2008). Mean

annual precipitation was approximately 900 mm (Retallack, 2007). Sediments weathering

from the mountains uplifting in the Cordilleran region were deposited across the northern part of the Great Plains region through eastward flowing streams, forming the Arikaree

Group, a mixture of volcaniclastics, eolian, fluvial and lacustrine deposits (Condon,

2005).

The second time slice comprises 5.5 million years and spans the late Barstovian age through the end of the Clarendonian age. This time slice begins after the Mid-

Miocene Climatic Optimum, as temperatures began to decline dramatically. Falling 62

temperatures fluctuated with an overall drop from 13°C to about 7.5-9.5°C (Cooke et al.,

2008). This interval of global cooling was mediated by the formation of permanent ice

sheets on Antarctica (Woodruff et al., 1981; Zachos et al., 2001; Rocchi et al., 2006;

Lewis et al., 2007). The development in the Late Cenozoic of a rainshadow from the

uplifting Cordilleran region in concert with the cooling temperatures resulted in increased

aridity in the Great Plains during the middle Miocene (Zubakov and Borzenkova, 1990;

Ward and Carter, 1999). Mean annual precipitation fluctuated between 1000 mm and 500

mm during this interval (Retallack, 2007). Eastward flowing streams continued to deposit sediment on the Great Plains forming the Ogallala Group, an eastward sloping wedge of coarse fluvial sediments that eroded from the Laramie and Front Ranges (Condon, 2005).

The Ogallala Group sediments include braided stream, alluvial fan, low relief alluvial plain, and lacustrine deposits (Goodwin and Diffendal, 1982; Scott, 1982; Swinehart and

Diffendal, 1989; Flanagan and Montagne, 1993).

The third time slice is 6.5 million years in duration and includes the Hemphillian through the Blancan ages, spanning the Miocene-Pliocene boundary. At the beginning of this time slice in the Miocene, temperatures stabilized at approximately 8°C in the early

Hemphillian and then continued to decline reaching a minimum of 4.5°C before rising back to 8°C by then end of the Miocene (Zachos et al., 2001; Cooke et al., 2008). This cooling was associated with aridity during the Miocene as mean annual precipitation dropped to 250 mm (Retallack, 2007). During the Pliocene, however, mean annual precipitation increased to approximately 1050 mm as temperatures continued to cool

(Chapin and Kelley, 1997; Cooke et al., 2008). Deposition of the Ogallala Group 63

continued during first half (late Miocene portion) of this time slice. Erosion of the

western mountain ranges slowed during the Pliocene; as deposition slowed, an

unconformity formed above the Ogallala Group (Condon, 2005). Furthermore, the Great

Plains region began to slowly uplift (Morrison, 1987). As the region rose, sediments in

the western Great Plains were stripped away and either redeposited on top of the Ogallala

Group or removed completely; however, sediments accumulated in Nebraska during the

Pliocene due to its northeastward slope at the time (Steven et al., 1997).

Species Occurrence Information

Species occurrence data were collected from the primary literature as well as

online databases (Miocene Mammal Mapping Project [MIOMAP] (Carrasco et al., 2005) and the Paleobiology Database [PBDB]). Species name, occurrence (latitude and longitude), and stratigraphic position were recorded for each species of Equinae

(Appendix C). I honored the reidentifications of several specimens in the PBDB record

performed by Alroy (2002, 2007) of the Paleobiology Database. The occurrence data was

split into the three times slices described above. Although species occurrence data was

collected for all species considered valid in recent phylogenetic hypotheses, such as

Hulbert (1993), Kelly (1995, 1998), Prado et al. (1996), and Woodburne (1996) (Fig. 1),

species with fewer than five spatially distinct occurrences in the study region per time

slice were excluded from the analysis. This cutoff number has been determined from

modeling experiments to be the minimum data required to produce robust GARP

analyses (Peterson and Cohoon, 1999; Stockwell and Peterson, 2002). 64

Environmental Data

A variety of environmental factors (e.g., temperature, climate, vegetation,

resource availability) may determine the ecological niche of a horse species. In order to

model niches of extinct species, environmental factors are estimated from sedimentary

variables collected from the sedimentary record (Stigall and Lieberman, 2005). Five environmental parameters representing vegetation, temperature, and precipitation were included in this study. Each of these parameters can be determined from the sedimentary record, either through fossils, or directly from the sedimentary rock. The combination of these variables creates a robust data set of environmental factors that influence the distribution of horses. The use of five environmental variables is consistent with standard

GARP methodology as analyses have been successful with as few as four and as many as

19 environmental factors (e.g., Anderson et al., 2002; Feria and Peterson, 2002; Peterson and Cohoon, 1999). Although covariation among these environmental variables exists

(e.g. vegetation and C4% or MAP and crocodile presence), GARP is not sensitive to

covariation among environmental variables because it is a Bayesian-based system that

produces accurate results for a wide range of domains, such as numerical function

optimization, adaptive control system design, and artificial intelligence tasks (Stockwell and Peters, 1999). Classical and parametric statistics, on the other hand, are sensitive to covariation within data and, therefore, are not applicable for this study. The five environmental parameters are discussed individually below. All data is presented in

Tables 3 and 4. 65

Stable Carbon Isotopes

During the Cenozoic, dominant vegetation shifted from leafy shrubs and trees (C3

plants) to grasslands (C4 plants). This shift in vegetation created a mosaic of food sources for equid taxa during the Miocene, resulting in a diverse range of morphological feeding adaptations in the Equinae clade (MacFadden, 1992; Webb et al., 1995). The distribution of a species’ food resource is primary factor determining its ecological niche and range

(Fox & Fisher, 2004; Lomolino et al., 2006). Carbon isotope composition (δ13C) can be

used as a proxy for vegetation type (C3 or C4) in the Great Plains. C3 and C4 plants have

different photosynthetic pathways (Calvin cycle and Hatch-Slack cycle, respectively) used for fixing atmospheric CO2 (Cerling and Quade, 1993). Each pathway fractionates

carbon isotopes to a different degree, producing non-overlapping carbon isotope

13 compositions. Modern C3 plants exhibit a δ C range of -22‰ to -35‰ with an average

of – 27‰ (O’Leary, 1988; Tieszen and Boutton, 1989), while modern C4 plants exhibit a

range of -10‰ to -14‰ with an average of -13‰ (O’Leary, 1988; Tieszen and Boutton,

1989). A third pathway, crassulacean acid metabolism (CAM), results in carbon isotope

compositions intermediate of the other two pathways, but it is primarily utilized by

succulent plants in arid conditions (Cerling and Quade, 1993) and uncommon in the study

area.

Stable carbon isotope data included in this study were assembled from published

literature sources that analyzed δ13C from either paleosols or tooth enamel of equids and proboscideans (Table 2). Paleosol stable carbon isotopes studies included in this analysis 66

applied an enrichment value of +14-17‰ to all values according to Cerling et al. (1989,

1991). Enamel studies applied an enrichment factor of +14‰ to all values according to

Cerling and Harris (1999). δ13C values also account for the 1.5‰ decrease of

atmospheric CO2 that has occurred since the onset of human fossil fuel burning (Friedli et

al., 1986). Raw stable carbon isotope data were converted into % C4 vegetation based on

Fox and Koch (2003) and Passey et al. (2002). Percent C4 vegetation was used as an

index of the vegetative composition. Low C4 percentages are interpreted as

predominantly leafy vegetation preferred by browsers, high percentages are interpreted as

predominantly grassy vegetation preferred by grazers and intermediate percentages

represent vegetation preferred by mixed feeders.

Mean Annual Precipitation

Rainfall directly influenced the vegetation available to equid species for feeding

and represents a fundamental parameter of a species’ ecological niche (e.g., Anderson et

al., 2002; Illoldi-Rangel et al., 2004). Mean annual precipitation (MAP) values

determined from paleosols, ungulate tooth size, and vegetation were compiled for

analysis (Table 2). The depth of the Bk horizon in paleosols can be utilized to estimate

MAP using the equation: P = 137.24 + 6.45D – 0.013D2 where D is depth in cm (Jenny,

1941; Retallack, 1994, 2005). MAP data estimated from ungulate tooth size within a community using “Per-species mean hypsodonty” (PMH), a measure of MAP developed by Damuth et al. (2002), was also included in this study. PMH is the average hypsodonty of the ungulate fauna divided by the number of all mammalian species present in a 67

community (Janis et al., 2004). Lastly, MAP ranges interpreted from plant assemblages

(Axelrod, 1985; Thommason, 1980) were utilized in this study.

Mollic Horizon

Soil horizons can provide information about precipitation, climate, and vegetation

cover. As discussed above, these factors influence the distribution of species. Modern

soils supporting grassy vegetation have a mollic epipedon, a surface layer consisting of

dark organic clayey soil about 2-5 mm thick (Retallack, 1997). In paleosols, mollic

epipedons are recognized by dark thin clayey rinds to small rounded soil peds along with fine root traces. In addition, fossilized mollic epipedons are nutrient-rich and often contain carbonate or easily weathered minerals. Retallack (1997, pers communication

2007) divided paleosols containing calcareous nodules from the Great Plains during the

Miocene into three categories. The first category, mollic, contained all paleosols that adhered to the above criteria. The second category, near mollic, was assigned to paleosols that had surface horizons with “a structure of subangular to rounded peds some 5-10 mm in size, along with abundant fine root traces and darker color than associated horizons”

(Retallack, 1997). Near mollic epipedons are found under bunch grasslands of woodlands or under desert grasslands (Retallack, 1997). The third category, non-mollic, was assigned to all other paleosols included in the study. This third group consisted primarily of paleosols similar to soils of deserts and woodlands (Retallack, 1997). The vegetation cover interpreted from the three categories of mollic epipedons were utilized and coded 1,

2, and 3, respectively. 68

Vegetation

The fourth environmental variable included in this analysis is ecosystem type as determined from paleobotanical studies (Table 2). Although an extensive collection of paleobotanical occurrences and taxonomic descriptions exist in the literature, only studies that included a paleoenvironmental description were included in the data set for this analysis. These environmental descriptions were coded and divided into four categories:

1) Woodland [e.g. “deciduous valley and riparian forests with scattered

grasslands” (Axelrod 1985)]

2) Savanna or subtropical grassland with surrounding wooded areas [e.g.

“subtropical grassland with associated mesic and woody components”

(Thomasson, 2005)]

3) Savanna or subtropical grassland [e.g. “grassland savanna” (Gabel et al.,

1998)]

4) Dominantly grassland/Steppe [e.g. “grassland, shrubs, with limited trees”

(Thomasson, 1990)]

Vertebrate Assemblages

In the fossil record, crocodiles have traditionally been used as paleotemperature proxies (Lyell, 1830; Owen, 1850). Based on ecological analysis of modern crocodilians, temperature is considered to be the most influential factor determining the distribution of modern crocodiles (Woodburne, 1959; Martin, 1984; Markwick, 1996). The dataset 69 used in this analysis is derived from the comprehensive work of Markwick (1996, 2007).

Markwick (1996) compiled a database of vertebrate assemblages from around the world and used the distribution of crocodiles as a paleotemperature proxy from the Cretaceous through the Neogene. Markwick (1996) includes crocodiles that belong to the “crown group” (Alligatoridae, Crocodylidae, and Gavialidae families). The climatic tolerance of the modern American alligator, Alligator mississippiensis, was used as the minimum climate tolerance of extinct crocodiles. Alligator mississippiensis can tolerate an average temperature range of 25-35° C. Because crocodiles are well documented in the fossil record and Markwick (1996, 2007) includes noncrocodillian vertebrate sites as a control group, crocodilian absences in his database are considered true absences. This study includes 95 assemblages from Markwick (2007) that fall within the study area. For this study, crocodilian presence and absences were coded 1 and 0, respectively.

Table 3.

Environmental data for each grid box in the middle time slice. Mollic Crocodile Long. Lat. % C4 MAP*(mm) Epipedon Vegetation Presence -102.5 43.5 - - - 3 (1) - -101.5 43.5 - 266.17 (1) 3 (1) 3 (11) - -100.5 43.5 - - - - 0 (1) -99.5 43.5 - 356.31 (17) 2.9 (17) 3 (9) 0 (1) -97.5 42.5 13 (1) - - - 1 (2) -98.5 42.5 16 (3) 1590.65 (1) - 2.5 (2) 1 (1) -99.5 42.5 18.4 (6) 819.07 (4) 2 (3) 3 (7) 0 (3) -100.5 42.5 10.6 (5) 519.57 (15) 2.1 (13) 3 (12) 1 (1) -101.5 42.5 15 (1) 825 (1) - 2.8 (4) - -102.5 42.5 16 (1) - - - 0 (1) -103.5 42.5 13.5 (3) 410.34 (9) 1 (8) - 1 (2) 70

Table 3: continued

-104.5 41.5 - 325.86 (1) - - 0 (1) -103.5 41.5 18.5 (2) - - - 0 (1) -102.5 41.5 28 (1) 479.59 (3) 2 (2) 2 (1) - -101.5 41.5 16 (1) - - - - -98.5 40.5 0 (1) 1888.09 (1) - - 0 (1) -100.5 40.5 23 (1) - - - - -103.5 40.5 - 1143.92 (1) - 1 (1) - -104.5 40.5 - 633.87 (1) - - - -100.5 39.5 21 (1) 402.61 (2) 2.5 (2) 2 (1) - -99.5 39.5 - 266.53 (1) - - 0 (1) -99.5 37.5 ------99.5 36.5 17.3 (3) - - - - -100.5 36.5 18 (1) 825 (1) - - 1 (1) -101.5 36.5 12 (1) - - - 1 (1) -100.5 35.5 5 (1) - - - 1 (2) -100.5 34.5 1 (1) 760 (1) - 3 (1) 0 (1) -101.5 33.5 29 (2) - - - -

* Mean Annual Precipitation Values in parathenses indicated the number of data points for the environmental variable in the specified grid box. Environmental data is averaged per grid box. Original values are described below: Mollic Epipedon: 1 = mollic, 2 = near-mollic, 3 = non-mollic Vegetation: 1= woodland, 2 = savanna with surrounding woodland, 3 = savanna, 4 = grassland/steppe Crocodile Presence: 0 = absence, 1 = presence

Table 4.

Environmental data for each grid box in the late time slice. Mollic Crocodile Long. Lat. % C4 MAP*(mm) Epipedon Vegetation Presence -98.5 43.5 59 (1) 323.53 (1) - - - -97.5 42.5 55 (1) 661.38 (2) - - 0 (1) -98.5 42.5 15 (1) 486.91 (2) - - - -99.5 42.5 37 (3) 379.16 (5) 1.8 (5) - 0 (1) -100.5 42.5 0 (1) 393.11 (1) 2 (1) - - 71

Table 4: continued

-101.5 42.5 58 (1) - - - - -103.5 42.5 12 (3) 533.87 (1) - - - -103.5 41.5 26 (2) 335.94 (6) 2.2 (6) - - -102.5 41.5 27 (5) 349.42 (23) 2.5 (22) 2.7 (3) - -101.5 41.5 19 (2) 339.2 (5) 2.3 (4) 2 (1) - -100.5 41.5 - 275.54 (1) - - - -99.5 41.5 15 (1) - - - - -98.5 41.5 21 (1) - - - - -97.5 41.5 69 (2) - - - - -100.5 40.5 12 (1) 820.2 (1) - - - -102.5 40.5 - 520.47 (1) - - - -101.5 39.5 - 646.52 (1) - 4 (1) - -100.5 39.5 - 429.28 (17) 1.6 (16) - - -99.5 39.5 - 365.76 (27) 2.3 (27) 2 (2) - -97.5 39.5 - 181.26 (1) - - - -99.5 38.5 - 252.52 (2) 3 (2) - - -100.5 38.5 - 356.51 (27) 2.9 (27) 2 (1) - -100.5 37.5 38 (2) 503.01 (42) 2.5 (41) - 0 (5) -99.5 37.5 8 (1) 148.43 (1) - - - -99.5 36.5 4 (1) - - - 0 (2) -100.5 36.5 9.5 (2) - - 3 (1) 0 (3) -101.5 36.5 - - - - 1 (1) -102.5 35.5 - - - - 0 (1) -101.5 35.5 37 (2) - - - 0 (3) -100.5 35.5 21 (1) - - - 0 (1) -99.5 34.5 - - - - 0 (1) -100.5 34.5 0 (1) - - - - -101.5 34.5 43 (3) - - - 0 (2) -102.5 34.5 20 (1) - - - 0 (1) -102.5 33.5 11 (1) - - - - -101.5 33.5 21.5 (2) - - - 1 (3) -100.5 33.5 - - - - 0 (1) -99.5 33.5 - - - - 1 (1)

Refer to Table 3 for explanation

Creation of Environmental Layers

For analysis of environmental data, the study region was divided into 1° grid

boxes using latitude and longitude coordinates. This method is equivalent to that

employed in modern GARP analyses (e.g. Stockwell and Peterson, 2002; Wiley et al.,

2003; Illoldi-Rangel et al., 2004). Environmental parameters derived from the literature,

as discussed above, were assigned to the appropriate grid box. If multiple data points

occurred in one grid box, the values were averaged to account for environmental

variability. This method of intermediate coding has been successful with GARP analysis

and is an effective method of representing environmental variability (Stigall Rode and

Lieberman, 2005). Original data is included in Appendix D. Although data was initially collected for an early Miocene time slice, niche modeling could not be performed for this time slice due to insufficient environmental data. Percent C4 and vegetation data only

covered two grid boxes, making interpolation (discussed below) impossible for these

environmental variables. The other three environmental variables from the early time

slice covered more than two boxes but did not cover the same range as the other two time

slices, making comparisons between time slices impossible. Lastly, occurrence data for species in the first time slice did not overlap spatially with the environmental coverage areas; therefore, the minimum number of five discrete occurrence points for each species was not met. While no biogeographic models could be constructed for the early time slice, this interval is included in discussions below. Consequently, niche models are produced for two time slices, representing the middle Miocene, the middle time slice, and late Miocene/early Pliocene, the late time slice. 73

Environmental data points for the middle and late time slices were imported into

ArcGIS 9.2 (ESRI Inc, 2006). An interpolated surface was created for each environmental variable using the inverse distance weight procedure. Four data points were used to create each interpolated surface with a power of 3 and an output cell size of

0.1 (8 x 11 km). Interpolation was based on four data points because this was the largest number of data points appropriate for interpolation that were available from all environmental data sets. The interpolated environmental area for the middle time slice and late time slice covered from 104°W 44°N to 98°W 34°N and 104°W 44°N to 97°W

33°N, respectively. An example of an interpolated environmental coverage is shown in

Figure 6.

Distribution Modeling

A genetic algorithm approach was chosen to model the distribution of Equinae species. Genetic algorithms have been successfully used in previous niche modeling analyses of paleontological data (Stigall Rode and Lieberman, 2005) because genetic algorithms are effective for data sets with unequal sampling and poorly-structured domains (Stockwell and Peterson, 2002). Other statistical methods such as multiple regression and logistic regression, assume multivariate normality and true absence data.

Because absence in paleontological data does not necessarily represent true absence and multivariate normality is unlikely with paleontological data, these methods are not suitable here. Genetic algorithms apply a series of rules in an iterative, evolving manner to the data set until maximum significance is reached (Stockwell and Peters, 1999). The 74

Figure 6. Examples of environmental variable interpolations. A) Stable isotope interpolation representing the percentage of C4 vegetation in the late time slice. B) Crocodile presence/absence interpolation for the middle time slice, 0 = absence, 1 = presence. See Figure 5 for base map explanation. 75

genetic algorithm program employed in this study, GARP (Genetic Algorithm using

Rule-set Prediction), was specifically designed to predict species ranges based on their

fundamental niche as estimated from environmental variables (Peterson and Vieglas,

2001). Another strength of the GARP modeling system is it was originally designed to

accommodate for data from museum collections, in particular GARP is able to

accommodate for non-uniformly distributed, sparse, or patchy data (Peterson and

Cohoon, 1999;

Stockwell and Peters, 1999). Furthermore, co-variance between environmental variables

does not negatively impact the model results (Stockwell and Peters, 1999).

All species distribution modeling was performed using DesktopGARP 1.1.4

(www.nhm.ku.edu/desktopgarp). GARP is composed of eight programs that include data

preparation, model development, model application and model communication

(Stockwell and Peters, 1999). The GARP system divides the data in half to create two groups, the test group and the training group. A rule (e.g. logit, envelope) is randomly selected and applied to the training set. The accuracy of the rule is assessed using 1250 points from the test data set and 1250 points randomly re-sampled from the area as a whole. The rule is then modified (mutated) and tested again. If accuracy increases, the modified rule is incorporated in the model, if not, it is excluded. GARP creates separate rule sets for each region within the study area, rather than forcing a global rule across the data. This results in higher accuracy and precision in resulting models than global rule methods (Stockwell and Peters, 1999; Stockwell and Peterson, 2002). The algorithm continues until further modification of the rules no longer results in improved accuracy or 76 the maximum number of iterations set by the operator is reached (Stockwell and Noble,

1992; Stockwell and Peters, 1999).

Prior to performing the modeling analysis, the statistical significance of each environmental variable was tested using a jackknifing procedure. This was done by selecting all combinations of rules and selected layers for the GARP analysis (Stigall

Rode and Lieberman, 2005). The five most abundant species (Cormohipparion occidentale, Neohipparion affine, Pliohippus pernix, Protohippus supremus,

Pseudhipparion gratum) were used from the middle time slice in the jackknifing procedure. The contribution of each environmental variable to model error, measured by omission and commission, was analyzed using a multiple linear regression analysis in

Minitab 14 (Minitab Inc., 2003). An environmental variable was inferred to increase error in the model if it was significantly correlated with either omission or commission. A multiple linear regression analysis was conducted for the five species in the middle time slice together as well as each individual species in the middle time slice. Although each environmental variable is significantly correlated to error with at least one species; no environmental variable contributed significant error with all species. Therefore, all variables were considered valid as environmental predictors and were included in the niche modeling analysis.

Niche modeling was performed individually for each species in each time slice.

All rules were selected to be used, as well as all environmental layers and 500 replicate models were run for each species with the convergence interval set at 0.01. Training points were set to 50% as discussed above. The best subset selection was utilized so that 77 the ten best models were chosen with an omission threshold of 10% and a commission threshold of 50%. Range predictions were output as ASCII grids and the ten best models were imported into ArcGIS 9.2. The ASCII grids were converted into raster files and weight-summed to derive the final range prediction maps (Figure 7). The geographic area occupied by each species was quantified for biogeographic analysis (Table 5).

Biogeographic Analyses

Examination of Distributional Patterns and Habitat Tracking

Habitat Fragmentation

The relative prevalence of patchy ranges, ranges in which a species’ distribution includes multiple discrete areas of occurrence, versus widespread continuous ranges was analyzed. Habitat fragmentation has been hypothesized to contribute to the radiation of numerous clades (e.g., birds: Mayr, 1942). If geographic patchiness does increase speciation rate, I should expect to see a higher number of patches in the predicted ranges of species in the middle time slice when speciation rates were higher, than those in the late time slice, when the clade was in decline. The number of discrete populations or patches occupied was counted for each species in each time slice (Table 5). The extent of a population or patch was defined by a contained area that did not have a continuous connection with a second population. The number of populations per species for each time slice was statistically analyzed using a Two-Sample T-Test (Table 6).

Range Shift and Habitat Tracking 78

Initial examination of range models indicated an apparent southernward shift of

species between the time slices. This apparent southward shift of species was analyzed

statistically. The study area for each species was divided in half along the 39°N latitudinal in the middle time slice and the 38.5°N latitudinal in the late time slice. For both time slices, the percent area occupied by each species was calculated using ArcGIS

(Table 5). A two sample T-Test was applied to determine whether species in the late time

slice occupied a statistically larger portion of the southern region of the Great Plains than

species of the middle time slice, indicating a range shift to the south (Table 7).

Only one species, Cormohipparion occidentale, was extant in both time slices. To determine whether the shifting distribution of C. occidentale from one time slice to

another was a function of habitat tracking, the niche model for the middle time slice was

projected onto the late time slice environmental layers (Peterson et al., 2001). If the

resulting distributional pattern matches the original predicted distribution of C.

occidentale for the late time slice, then C. occidentale tracked its preferred habitat from

the middle time slice to the late time slice (i.e., niche conservatism). If the distributional

patterns do not have a high degree of overlap, C. occidentale did not occupy the same

niche in both time slices, and therefore the species would be interpreted to have altered its

fundamental niche through time (i.e., niche evolution). To determine whether the

distributions were equivalent, the area overlap was measured in ArcGIS and compared to

the area not shared as a percentage. 79

Table 5.

Geographic ranges predicted for species in the middle and late time slices from GARP Modeling. 80

Examination of Species Survival versus Range Size

Whether a general relationship between species longevity and predicted

distribution area occurs was also assessed through a regression analysis (Table 8).

Specifically, the general pattern that species with larger range sizes live longer was tested. The longevity of each species was determined from the literature as illustrated in the stratocladogram in Fig. 1.The relationship between species survival across North

American Land Mammal Age (NALMA) divisions and the geographic extent of a

species’ distributional range was also examined. Statistical analyses were performed for

each Land Mammal Age division within the temporal extent of this study

(Barstovian/Clarendonian, Clarendonian/Hemphillian, and Hemphillian/Blancan).

Survival across the boundary was compared to the size of the species’ predicted range.

The area of each species range was determined within ArcGIS by calculating the sum of

the areas in which seven or more of the ten best models predict occurrence (Table 5).

Previous methods have summed three of the five best (Lim et al., 2002), six of the ten

best (e.g., Stigall Rode and Lieberman, 2005), and all of the ten best (Peterson et al.,

2002; Nunes et al., 2007), so our approach is more conservative. Raw area counts were

converted into percentage of total model areas for the time slice because the extent of the

niche modeling area is different between time slices (Table 5). A nonparametric

statistical method, Kruskal-Wallis, was used to analyze the relationship between survival

and area because the data are not normally distributed even after log, square root, and

arcsine transformations were applied (Tables 9, 10, 11).

Results and Discussion

Ranges were predicted for 18 species from the middle time slice and 13 species

from the late time slice (Table 1). Predicted ranges for the middle and late time slice are

included in Appendix E.

Habitat Fragmentation

During the middle time slice, predicted species ranges were divided into more

populations or patches than during the late time slice (Two-Sample T-Test, p=1.15x10-4)

(Table 6). The relative abundance of patchy habitats in the middle time slice correlates with the mid Miocene interval of rapid cooling. Speciation was high during the middle time slice and the Equinae clade reached its highest diversity at this time (MacFadden,

1992; Hulbert 1993). Fragmentation of habitats led to patchy distributions. This in turn led to niche partitioning and speciation via vicariance, giving rise to the diverse group of mixed feeders, browsers and grazers that inhabited the mosaic of vegetation in the Great

Plains (Webb et al., 1995).

The more continuous species ranges of the late time slice may be the result of spreading grasslands. Environmental coverages of the middle time slice show an area of low precipitation, high percentages of C4 plants, and an absence of crocodiles that spans

across the central part of the Great Plains (Fig. 6b). In several predicted ranges for the

middle time slice, this area is not occupied (Fig. 7a). The environmental coverages for the

late time slice indicate a return to more wet conditions in this area and a more uniform environmental distribution throughout the study area. Predicted species ranges in the late 82 time slice include this area resulting in more continuous ranges from the northern to southern part of the study area (Fig. 7b). Chapin and Kelley (1997) reported increased precipitation in the Pliocene based on the establishment of drainage systems, the erosion of Mesozoic and Cenozoic sediments, the opening of previously closed basins and stable isotope compositions of paleosol carbonates in arid lands. Approximately 6-7 Ma, grasslands expanded into wetter climatic regions (Retallack, 1997). As grasslands spread throughout the Great Plains in the Late Miocene and Pliocene, habitats became more homogeneous (Axelrod, 1985; Webb et al., 1995). The available range for species adapted for open grassland and steppe habitats increased, creating large continuous distributions. Continuous ranges may have reduced speciation (Hulbert, 1993) within the clade due to lack of vicariant barriers, a pattern previously observed in Devonian marine taxa (Stigall, 2008). While the diversification of the Equinae clade has been attributed to habitat fragmentation and niche partitioning (MacFadden, 1992), its decline has been attributed to the inability of species to adapt to climatic deteriorations during the Late

Miocene and Pliocene (Webb, 1983; MacFadden, 1992). However, lower speciation rates due to the increase in continuous habitat availability following the spread of grasslands, may have also been influential in the decline of the clade. Hulbert (1993) observed high extinction rates in the late Miocene coupled with low speciation rates that eventually reached zero.

Table 6.

Two-Sample T-Test comparing number of discrete populations per time slice. Source Sample Size (N) Mean Standard Deviation SE Mean Middle 18 2.389 0.698 0.16 Late 13 1.308 0.630 0.17

T statistic = -4.50 p = 1.154x10-4 Degrees of Freedom = 24

Habitat Tracking

As temperatures decreased during the Miocene and the climate became more arid,

several species adapted to wooded savannas rather than open grasslands retreated to

warmer and wetter regions of North America, specifically the southern Great Plains and

Gulf Coast regions (i.e., Nannippus aztecus and Nannippus peninsulatus; Fig. 7c,d)

(Webb et al., 1995). Based on data from carbonate nodules, Retallack (2007) determined

that a climatic gradient from warm and humid in the coastal regions to cool and arid in

the northern Great Plains region existed. Species of Equinae in the late time slice of this study occupied larger ranges south of 38.5°N latitudinal, than species of the middle time slice below 39°N latitudinal (Two Sample T Test P = 0.009) (Table 7). This southernward shift indicates that species may have tracked their preferred habitat to the south as climate changed more drastically in the northern regions of North America.

Closer examination of morphological differences due to diet type between the species will result would further test this hypothesis. 84

Figure 7. GARP predicted species distribution maps for (A) Pseudhipparion gratum in the middle time slice and (B) Nannippus lenticularis, (C) Nannippus aztecus, and (D) Pseudhipparion peninsulatus in the late time slice. The range prediction key indicates how many of the ten best subset maps predict species to occur at a location. See Figure 5 for base map explanation. 85

Table 7.

Two-Sample T-Test comparing the area of a species’ geographic range in the Southern Great Plains per time slice. Source Sample Size (N) Mean Standard Deviation SE Mean Middle 18 20.80 20.40 4.8 Late 13 35.69 7.62 2.1

T statistic = -2.84 p= 0.009 Degrees of Freedom = 23

By the Hemphillian, the southwestern region of North America was semi-arid and

was dominated by shrubland vegetation (Axelrod, 1985). Many ungulates retreated from

this region into the Great Plains (Webb et al., 1995). This included five species that were

modeled in the late time slice: Dinohippus leidyanus, Dinohippus interpolatus, Equus

simplicidens, Astrohippus ansae, and Astrohippus stockii (Maguire and Stigall, In review). Maguire and Stigall (In Press) determined that speciation of these five taxa was a result of geodispersal across the Rocky Mountains from the Southwest to the Great

Plains. Predicted distributional ranges of the five species are similar and occur predominantly on the western edge of the Great Plains region (Fig. 8). During the

Neogene, the uplift of the Rocky Mountains was interrupted by intervals of tectonic quiescence (Condon, 2005). The distributional patterns predicted from niche modeling supports the conclusion of Maguire and Stigall (In Press) that speciation of these five species was a result of a cyclical geodispersal process as habitat tracking occurred across

the Rocky Mountains. 86

Figure 8. GARP predicted distribution maps for (A) Astrohippus ansae and (B) Dinohippus interpolatus in the late time slice. See Figure 5 for the base map explanation and Figure 7 for range prediction explanation. 87

As previously mentioned one species, Cormohipparion occidentale, was extant

during both the middle and late time slices. The species predicted distributions are

presented in Figure 9a and 9c for the middle and late time slice, respectively. Any GARP

model, for example the middle time slice GARP model, is based on the relationship

between a species and its preferred habitat. This same relationship can be used to predict

a species distribution for another time slice, for example the late time slice. The percent

overlap of the original prediction by the middle GARP model and the new prediction for

the late time slice indicates how the relationship between the species and its preferred

habitat remained the same between both time slices. The consistency of this relationship

can be referred to as habitat tracking. Projection of the GARP model for the middle time

slice onto the environmental layers of the late time slice produced a distribution that

covered 48.85% of the area originally predicted for the late time slice (Fig. 9b,c). This

percentage of overlap suggests that Cormohipparion occidentale tracked its preferred

habitat from the middle time slice into the late time slice. In addition, projection of the late time slice GARP model onto the middle time slice environmental layers produced a

distribution that was 52.21% similar to the original distribution for the middle time slice

(Fig. 9a,d). The predicted distributional maps show during the middle time slice, the

species’ niche does not occupy the central region of the study area (Fig. 9a). In the late

time slice, however, the predicted range does cover this central area, indicating that C.

occidentale spread through this region as it tracked its habitat (Fig. 9c). Unlike other

genera of Equinae, Cormohipparion migrated to the Old World during the Miocene along

with the genus Hipparion (Skinner & MacFadden, 1977; MacFadden, 1992). 88

Figure 9. GARP prediction maps for Cormohipparion occidentale. A) Predicted distribution for the middle time slice. B) Predicted distribution when the middle time slice model is projected onto the late time slice. C) Predicted distribution for the late time slice. D) Predicted distribution when the late time slice model is projected onto the middle time slice. See Figure 5 for base map explanation and Figure 7 for range prediction explanation. 89

Cormohippairon also was one of the last genera remaining in North America at the end of the Miocene (C. emsliei survived in the coastal regions through the Blancan). The combination of its longevity and large range may be a result of its ability to track its preferred habitat.

Range Size vs. Survival

A positive relationship between geographic range size and species longevity occurs in many clades (Stanley, 1970; Vrba, 1987; Rode and Lieberman, 2004;

Hendricks et al., 2008). This relationship has not been quantitatively assessed in prior analyses of equid biogeography; however, statistical analysis of this relationship is possible based on niche models constructed in this study. No significant relationship between predicted range size and longevity was recovered when all species ranges modeled from both time slices were combined in a single regression analysis (Table 8, p

= 0.670). However, when the size of species’ geographic range was compared with survival or extinction across specific boundaries between NALMA divisions, significant relationships were uncovered. The NALMA divisions (Alroy, 2003) are based on first and last appearance data of all mammals in North America and are neither dependent on

“immigrant first appearance datum” nor heavily dependent on geochronology data.

Species living in the Barstovian that survived into the Clarendonian had statistically larger ranges than species that became extinct by the end of the Barstovian (Kruskal-

Wallis Test, p = 0.013) (Table 9). Clarendonian species that survived into the

Hemphillian did not have significantly larger ranges than species that became extinct 90

(Kruskal-Wallis Test, p = 0.183) (Table 10). Furthermore, Hemphillian species that survived into the Blancan did not have significantly larger ranges (Kruskal-Wallis Test, p

= 0.571) (Table 11). This last result may be a function of small sample population as only

11 species in this study were extant during the Hemphillian.

Table 8.

Linear Regression Analysis of species longevity and the area of a species’ geographic range. Predictor Coefficient SE Coefficient T P Constant 2.84 0.81 3.51 0.001 Area 0.01 0.03 0.43 0.670

Longevity = 2.84 + 0.01(Area) S = 1.66 R-Sq = 0.6%

Table 9.

Kruskal-Wallis Test comparing the area of a species’ geographic range versus species survival across the Barstovian/Clarendonian Boundary. Source Same Size (N) Median Average Rank Z Value Survival 9 27.93 11.1 2.49 Extinct 7 13.70 5.1 -2.49

H = 6.19 p= 0.013 Degrees of Freedom = 1

Table 10.

Kruskal-Wallis Test comparing the area of a species’ geographic range versus species survival across the Clarendonian/Hemphillian Boundary. Source Same Size (N) Median Average Rank Z Value Survival 10 30.77 15.4 1.33 Extinct 15 24.28 11.4 -1.33

H = 1.77 p = 0.183 Degrees of Freedom = 1

Table 11.

Kruskal-Wallis Test for comparing the area of a species’ geographic range versus species survival across the Hemphillian/Blancan Boundary. Source Same Size (N) Median Average Rank Z Value Survival 4 42.87 6.8 0.57 Extinct 7 32.91 5.6 -0.57

H = 0.32 p = 0.571 Degrees of Freedom = 1

The relationship between survival from one NALMA to another and species range size may be a function of climate and vegetation change. In the Miocene, temperatures dropped quickly from 13°C to 7.5-9.5°C during the Barstovian (Zachos et al., 2001;

Cooke et al., 2008). During this interval of climate change, vegetation cover was shifting and patchy. Under those conditions, the range size of individual species was important for survival into the Clarendonian. Species with larger ranges and broader ecological tolerances were better adapted to the changing environment. Those with smaller ranges and more restricted ecological tolerances could not adapt. During the late Miocene, 92 however, species range size was irrelevant to survival. Temperatures continued to drop to approximately 2.3°C during the Clarendonian and Hemphillian, accompanied by decreasing MAP that reached 500 mm (Zachos et al., 2001; Retallack, 2007; Cooke et al.,

2008). Climatic deterioration became too severe even for those species with large ranges and broad ecological tolerances to survive. Precipitation increased in the Pliocene and grasslands spread into areas with more moisture. Only species that were adapted to the spreading grassland habitat exhibited large geographic ranges and survived into the

Pliocene.

Regional Trends

The Great Plains is analyzed as a case study for niche modeling. Equinae species, however, inhabited other regions of North America during the Miocene, and dispersal between these regions was frequent. The distributional patterns that resulted influenced the speciation of the clade (Maguire and Stigall, In Press). Here I briefly discuss how regional patterns and local (ecological) patterns are related in the Great Plains region.

Pliohippus mirabilis had a patchy habitat in the Great Plains during the middle time slice (Fig. 10a) that covered 24.3% of the study area. Pliohippus mirabilis evolved into P. pernix through anagenetic speciation (Hulbert, 1993). The patchy pattern of P. mirabilis supports the interpretation that vicariance due to habitat fragmentation led to the speciation of P. pernix. Pliohippus pernix had a continous range throughout the Great

Plains during the middle time slice that covered 43.4% of the study area (Fig. 10b). This broadly distributed and adapted species dispersed to the Gulf Coast in the middle time 93 slice (Maguire and Stigall, In Press). In the Great Plains P. pernix evolved into P. nobilis anagenetically (Hulbert, 1993). Pliohippis nobilis had a patchy predicted distribution in the Great Plains that covered 28% of the total area (Fig. 10c). Although it has a predominantly southern distribution in the Great Plains, this species remained in the

Great Plains during the late Miocene and did not disperse to other regions of North

America and became extinct by the Pliocene. The patchy habitat of P. nobilis may illustrate the lack of suitable habitat for the species in the Great Plains. Due to its inability to migrate to other regions of North America, for example the Gulf Coast, it became extinct in the early Hemphillian (Fig. 1).

The combination of regional and local distribution patterns provides a more complete picture of the biogeography and evolution of Equinae during the Miocene than either does alone. Here, Pliohippus provides an example of how the local distribution pattern is consistent with the regional pattern. The five species previously discussed that migrated into the Great Plains from the southwest are another example of how the local pattern supports the regional pattern. Their western predicted distribution pattern in the

Great Plains suggests they or their ancestors dispersed from the southwestern region of

North America. Maguire and Stigall (In Review) concluded the same five species in the

Great Plains speciated through geodispersal from their ancestors in the southwest.

Figure 10. GARP predicted species distribution maps for (A) P. mirabilis, and (B) P. pernix in the middle time slice and P. nobilis in the late time slice. See Figure 5 for base map explanation and Figure 7 for range prediction explanation. 95

Conclusions

Equid species of the middle Miocene comprised a higher number of discrete populations than late Miocene-early Pliocene species. Diversification of the Equinae

occurred just prior to the middle Miocene indicating speciation coincided with the

distribution of patchy habitats. Habitat fragmentation resulted from changes in vegetation of the Great Plains as the climate began to deteriorate. Following dramatic cooling in the

Barstovian, species with larger ranges preferentially survived compared to species with

smaller geographic distributions. During the late Miocene, however, when temperatures

were even cooler, and the climate more arid, species range size was irrelevant to survival.

The dichotomy between these intervals may reflect differential response of species to rate

of climatic deterioration (rapid vs. gradual) or that a climatic threshold had been passed

following the Barstovian which affected specialists and generalists equally. Some

species, such as Cormorohipparion occidentale, exhibited niche conservatism (habitat

tracking) within the Great Plains as the climate deteriorated. Other species, such as

Dinohippus interpolatus and Astrohippus ansae, tracked their preferred habitats from the

southwestern region of North America to the Great Plains, while others, such as

Pliohippus pernix, tracked their preferred habitats from the Great Plains to the Gulf

Coast (Webb et al., 1995). Within the Great Plains region, distributional patterns show

invasion of species from the southwest and an overall southward shift towards the Gulf

Coast.

Species ranges were more continuous during the late Miocene to early Pliocene

than during the middle Miocene. More continuous ranges may have led to a decrease in 96

speciation rate of the clade due to lack of subpopulation isolation. Low speciation rate

coupled with increased extinction rate from the deteriorating climate resulted in the

decline of Equinae in North America. While Equus thrived on the Great Plains during the

Pliocene and into the Pleistocene, other genera such as Cormohipparion and

Pseudhipparion retreated to the coast, however, these species became extinct by the end

of the Pliocene.

Finally, niche modeling of horse species in this study has produced a quantitative,

detailed framework in which to analyze further hypotheses about the relationship between morphology, ecology, and evolution. Niche modeling of species ranges in the

Gulf Coast region would provide further insight into the final decline of the clade. In addition, matching morphological characteristics of individual species with the environmental parameters of their predicted niches would provide more detailed information about niche partitioning and habitat tracking during the Miocene. For example, examining the muzzle morphology of species in this study that showed significant migration southward versus those that did not, may demonstrate whether all species migrated south or only those not specialized in open grassland grazing. This study is the first quantitative analysis of ecological biogeography using ENM in a vertebrate fossil clade. Results of this study support ENM as an effective tool for modeling the ranges of fossil vertebrate species and which allows analysis of biogeographic patterns

within a hypothesis testing framework. 97

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CHAPTER 4: CONCLUSION

Previous work on the evolution of Equinae has primarily focused on the morphological differences between species. The combination of phylogenetic biogeography and ecological niche modeling employed in this thesis provides an in-depth understanding of the biogeography and evolution of the Equinae clade within a paleoecological framework. Biogeographic analyses, in general, provide insight into the interaction between an organism and its environment (Lomolino et al., 2006). Together, the biogeographical analyses used here examined how both ecological and historical factors of the environment influenced the evolutionary patterns of Equinae. In addition, they examined the biogeography of Equinae at the regional and local level, so that general distributional patterns could then be examined on a finer scale and distributional patterns at a fine scale could be placed in a regional context.

Specifically, the phylogenetic biogeographic analysis in Chapter 2 examined how historical variables, such as tectonic activity and climatic setting influenced the evolution of the clade. The results indicate that the changing climate during the Miocene was the primarriver of speciation within the clade. The cyclical patterns associated with the climate change resulted predominantly in speciation by geodispersal as climatic barriers rose and fell between regions of North America. The phylogenetic biogeographic study also provided historical information about relationships between the four regions in the study. The Great Plains and Southwest regions were the most recent regions to be separated through vicariance and also most recently experienced dispersal between them.

This relationship is consistent with the geological setting of the Miocene. Compressional 107

tectonism off the Pacific coast resulted in uplift of the Rocky Mountains in pulses of

active uplift and tectonic quiesence, promoting cyclical dispersal patterns, or

geodispersal, between the two regions.

In Chapter 3, ecological niche modeling was used to examine the distribution and evolution of equids at the ecosystem level in the Great Plains. The changing climate

resulted in patchy vegetation and habitat fragmentation in the Great Plains during the

middle Miocene. This distributional pattern occurred simultaneously with the radiation of

the Equinae, suggesting vicariant speciation due to habitat fragmentation was a primary driver of speciation that occur within the Great Plains. As climate cooled dramatically during the middle Miocene, species with larger geographic ranges were more successful in surviving from one NALMA to another while species with small ranges became extinct. As climate continued to deteriorate, however, differential range size no longer conferred a survival benefit. Those species that could, tracked their habitat. By the early

Pliocene, the preferred habitat of the majority of species was no longer present in the

Great Plains. Only those species adapted to steppe habitats thrived, such as Equus simplicidens, an ancestral species of the modern horse. Other species migrated to other regions of North America or became extinct.

Predicted species distributions from niche modeling are consistent with regional patterns observed from the phylogenetic biogeographic analysis. Five species determined to have dispersed into the Great Plains from the Southwest in Chapter 2, occupy ranges on the western margin of the Great Plains in their predicted distribution in Chapter 3. In addition, there is an overall southward shift of predicted species ranges from the GARP 108

analysis. Retreat to the Gulf Coast region by several mammalian groups has been

suggested previously (Webb et al., 1995) and both the phylogenetic biogeographic and

niche modeling analyses support this hypothesis.

In conclusion, climatic change was the primary factor influencing the radiation

and decline of the Equinae clade. Climate affected the distribution and evolution of

equids at local and regional levels from both a historical and ecological biogeographic

perspective. Although it has been previously hypothesized that the evolution of the

Equinae clade was the result of climate change (e.g., MacFadden, 1993; Hulbert, 1993;

Webb et al., 1995), this is the first study to use quantitative biogeographic methods incorporating statistical methods and models to test it. This study represents the first use

of ENM on an extinct continental clade and the first use of phylogenetic biogeography on

fossil mammals. The results of this thesis demonstrate the potential for both methods in

paleontology. By analyzing paleobiogeographic patterns within a quantitative historical

and ecological framework, studies such as this, which focus on the role of climate change

in driving the evolution of a clade can provide baseline information for studies of the modern biodiversity crisis. These methods are particularly helpful for conservation

studies that can use them to determine how climate change will affect the distribution of

endangered species as the modern climate changes and habitat degradation continues in

the modern world. 109

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APPENDIX A: VICARIANCE AND GEODISPERSAL MATRIX

Biogeographic character states for the Lieberman-modified Brooks Parsimony

Analysis data matrix for the vicariance and geodispersal analysis. Ancestor refers to the ancestral biogeographic region of the subfamily Equinae. Character states are nodes and terminal taxa of the clade. Absence of the taxa in a region is represented by 0. Presence of the taxa is coded 1. The derived condition is represented by 2. 111

112

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS

Geographic location data for all species belonging to Equinae in the Great Plains, along with the formation it was found in, the age of the site and the time slice it belonged to. Ages are given in NALMAs with the following abbreviations: E – early, M – middle,

L – late, AK – Arikareean, HMF – Hemingfordian, BAR – Barstovian, CLAR –

Clarendonian, HP- Hemphillian, BLAN – BLAN. Only species with 5 or more geographically distinct locations were used in the GARP analysis.

125

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS

allala MCLA Middle allala MCLA g O r ogan Ogallala Group LBAR Middle Middle Middle LBAR Group LBAR Group ogan Ogallala ogan Ogallala County Formation Age Time Slice County Formation Age Time Slice Keya Paha Ash Hollow CLAR Middle Beave K OK Roger Mills Ogallala Roger OK Middle CLAR -99.31 -99.31 KS Phillips Hollow Ash Middle EEHP -100.24 -100.24 Cherry NE Hollow Ash Middle CLAR r 43.16 -100.55 SD Todd Ash Hollow CLAR Middle Hollow CLAR Todd Ash SD -100.55 r 43.16 36.45 -100.02 O -100.02 36.45 y uarr Q Durham 35.51 -99.57 Kennesaw II Uhl Pit W Sand Canyon of 1 mi. Durham 35.51 40.59 -103.29 40.59 CO -103.30 40.47 Logan CO -103.56 L CO Pawnee Creek Weld LBAR Ogallala Group Middle LBAR Middle Eubanks 40.52 -103.55 CO Weld Pawnee Creek LBAR Middle Middle LBAR Creek Pawnee Weld CO -103.55 40.52 Eubanks Pawnee Buttes 3 Points Pit and Mastodon Quarry Horse West Quarry Quarry Bridge Norden A Railway Quarry Quarry Verdigre 40.49 Devil's Gulch Horse Quarry Off Devil's Jump Quarry -104.04 40.49 Nenzel Quarry CO Quarry Sawyer 42.47 -103.58 Quarry Schoettger 40.51 42.42 Weld Kennesaw I -100.02 40.49 CO 42.50 -104.00 -99.47 42.49 NE Weld 42.29 -104.04 -100.31 CO -101.17 NE Brown -98.08 CO NE Weld Pawnee Creek NE Brown 42.48 Weld Cherry NE 42.57 42.41 Cherry Pawnee Creek -101.08 Knox Valentine -99.42 -100.51 LBAR Pawnee Creek NE Valentine 40.59 Middle NE Valentine NE Pawnee Creek Cherry Valentine -103.29 LBAR Cherry Keya Paha Middle Valentine CO LBAR LBAR Middle L Middle LBAR Valentine Valentine LBAR Middle Valentine LBAR Middle LBAR Middle Middle LBAR Middle LBAR LBAR Middle LBAR Middle Middle Soldier Creek no. no. 6 Creek Soldier no. 10 Creek Soldier no. 17 Creek Soldier Mound Spirit Jack Swayze Quarry V526 Creek Wolf V527 Creek Wolf V529 Creek Wolf 43.00 43.00 V5324 Creek Wolf 43.00 V5325 Creek Wolf -100.00 -100.00 V5328 Creek Wolf -100.00 V5329 Creek Wolf 37.22 SD SD V5333 Creek Wolf 43.00 SD -99.47 Todd 43.00 Butte Gap) Turtle (West Todd 43.00 Canyon Big Spring -100.00 Todd -102.24 43.00 Canyon Big Spring KS 43.00 -102.23 Canyon Big Spring SD 43.00 SD -102.24 Clark Canyon Big Spring -102.24 43.00 SD Todd -102.24 Shannon 43.01 SD 43.04 SD -102.24 Shannon 43.00 SD -102.24 Shannon -99.50 Shannon SD -102.27 43.07 Shannon Ogallala SD Ash Hollow 43.07 SD Shannon SD -101.56 Ash Hollow 43.07 Shannon -101.56 Ash Hollow 43.07 Tripp Ash Hollow Shannon SD -101.56 Ash Hollow SD -101.56 Bennett Ash Hollow SD CLAR Bennett Ash Hollow SD EEHP Middle CLAR Bennett Ash Hollow Valentine Middle Late CLAR Bennett Middle CLAR Middle Middle Ash Hollow Middle CLAR Middle Ash Hollow Middle CLAR Ash Hollow Middle CLAR Ash Hollow Middle CLAR Middle Middle ECLA CLAR Middle Middle CLAR Middle CLAR Middle CLAR Middle Gallup Gulch Bear Quarry Hollow Horn Long Island Quarry 43.09 -101.06 39.54 42.49 SD -101.44 Todd NE Cherry Ash Hollow Ash Hollow CLAR Middle CLAR Middle Whisenhunt Whisenhunt Little Beaver B A Big Beaver Rim Locality North Crooked Creek Locality 42.55 42.55 42.55 42.55 -100.24 -100.27 -100.26 NE NE NE Cherry Cherry Cherry Ash Hollow Ash Hollow Ash Hollow CLAR CLAR Middle CLAR Middle Middle Canyon of Little White Rive B Above Burge B Leptarctus StadiumMcGinley's Fat Chance Locality 42.44 42.45 42.48 -100.49 42.53 -100.09 -100.02 NE -100.15 NE NE Cherry NE Brown Cherry Ash Hollow Ash Hollow Ash Hollow CLAR CLAR Middle Middle CLAR Middle Bluejay Quarry Quarry Kepler Shore North Creek Lonergan Big Toad Beach Quarry Poison Ivy Quarry Chokecherry River Valley Niobrara Quarry Kilpatrick 42.23 Olcott Hill Olcott Quarry 41.40 -98.06 Above Middlebranch 41.16 41.16 -102.48 Clayton Quarry East 41.17 42.25 NE 42.28 Wade Quarry -101.48 42.54 -101.48 NE Balanced Rock Quarry -101.51 -98.09 Antelope -98.05 Quarry Machaerodus NE -100.29 Morrill NE 42.10 Quarry Xmas NE NE Keith Kat Quarry East NE NE Keith -103.43 42.33 Keith Quarry Hans Johnson Ash Hollow Antelope Cherry Knox 42.41 Quarry Leptarctus 42.09 42.10 -98.10 NE Ash Hollow Kat Line Quarry 42.53 -99.55 -103.43 Kat Quarry Line Quarter -103.43 Sioux 42.53 NE Ash Hollow -100.14 Kat QuarryWest Line Ash Hollow Ash Hollow 42.43 Ash Hollow NE NE 29) Wakeeney (KU Loc. NE Ash Hollow Knox -100.14 CLAR Ash Hollow NE Quarry Minium -100.50 Sioux 42.53 Sioux Brown Middle CLAR 42.53 NE 42.53 Cherry NE Snake Creek -100.13 Middle 42.53 42.53 -100.14 Cherry -100.13 CLAR CLAR CLAR Cherry NE -100.14 CLAR 42.53 42.53 Middle -100.15 Ash Hollow 39.05 CLAR Middle Middle NE NE CLAR Ash Hollow Middle Snake Creek Snake Creek Middle Cherry Ash Hollow -100.14 -100.14 NE -99.45 Middle NE Cherry Cherry CLAR Ash Hollow Cherry NE NE Cherry Ash Hollow Middle 39.24 KS Cherry Cherry CLAR -100.08 Trego Ash Hollow CLAR CLAR CLAR Middle Hollow Ash Ash Hollow CLAR Middle Middle Middle KS Hollow Ash Ash Hollow Middle CLAR CLAR Graham Middle Ash Hollow Ash Hollow Middle Ogallala CLAR CLAR CLAR Middle Middle CLAR Middle CLAR Ash Hollow Middle Middle CLAR CLAR Middle Middle MCLA Middle LEHP Late arion occidentale occidentale arion pp Cormohipparion quinni quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion occidentale Cormohipparion Genus Species Site Name Lat Long State Name Long Lat Site Genus Species sphenodus Merychippus sphenodus Merychippus sphenodus Merychippus sphenodus Merychippus sphenodus Merychippus quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion quinni Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Genus Species Site Name Lat Long State Name Long Lat Site Genus Species Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohi

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS County Formation Age Time Slice Ellis Ogallala EEHP Late Ellis Ogallala EEHP Hemphill Beds Hemphill Late ELHP Wallace Ogallala Late ELHP TX Armstrong Goodnight Beds Beds Armstrong TX Goodnight Late ELHP TX Hemphill Hemphill TX Ogallala Late EEHP TX Lipscomb TX Lipscomb TX Ogallala Ogallala Late EEHP Late EEHP 100.42 TX Donley Donley TX 100.42 Beds Middle Clarendon MCLA -101.07 TX Crosby Crosby TX -101.07 Couch Middle MCLA -101.07 TX Crosby Crosby TX -101.07 Couch Middle MCLA -99.38 OK Roger Mills Ogallala -99.38 Roger OK Middle CLHE Axtel 34.55 -101.42 TX Randall Goodnight Beds LLHP Late Late LLHP Beds Goodnight Randall TX OK -101.42 -99.57 Axtel 34.55 Janes Quarry Janes Quarry Citellus dotti Site Arnett 36.07 33.25 36.55 33.25 -101.28 -100.15 -101.28 TX OK TX Crosby Beaver Crosby Bridwell? Ogallala Bridwell? EEHP LLHP EEHP Late Late Late Santee 42.49 -97.51 NE Knox Ash Hollow LLHP Late Late Late LLHP ELHP Hollow Hollow Late Ash Ash ELHP Knox Antelope Ogallala Texas NE NE OK -98.07 -97.51 Quarry Uptegrove Honey Creek -101.22 42.23 Mailbox Santee 42.49 Devil's Nest Airstrip Quarry fricki Amebelodon Aphelops Quarries Wakeeney (UM-K6-59) 41.15 Quarry Edson Quarry Lost -102.54 40.23 Rhinoceros Hill 42.41 42.49 36.45 Optima NE -100.15 Quarry North -98.39 -97.43 39.05 Coffee Ranch Quarry Cheyenne NE 42.12 Fauna Goodnight General -99.45 NE texanus Site Capromeryx NE Frontier -103.47 Holt Ash Hollow Knox KS 39.09 NE 39.07 Trego 38.47 Sioux -101.30 34.57 Ash Hollow 35.44 -101.30 36.02 -101.29 KS -101.11 39.20 -100.31 Ash Hollow Ash Hollow ELHP -100.31 KS KS Sherman -101.44 TX Late Ogallala Snake Creek Wallace LEHP KS Late Ogallala Sherman ELHP LLHP Late Ogallala Late LEHP MCLA Late Ogallala Middle ELHP Late ELHP Late ELHP Late Wray 40.04 -102.13 CO Yuma Ogallala Group LEHP Late Late LEHP Group Ogallala Yuma CO -102.13 Janes Quarry 42441) Formation (TMM Bridwell 40.04 Wray Wild Horse Creek #1 33.40 -101.11 TX Lubbock 33.25 35.47 -101.28 Bridwell TX Crosby ELHP Bridwell? Late EEHP Late Upper Couch Formation (TMM 947) 947) (TMM Couch Formation Upper 33.39 Sebits Ranch Locality 24-B Box T 42433) (TMM Couch Formation Lower 33.40 36.05 -100.00 36.14 -100.05 TX Lipscomb Ogallala (Hemphill Beds) LEHP Late Gidley's 3-toed Horse Quarry Quarry Horse Gidley's 3-toed Sebits Ranch Locality 24-A 35.06 36.05 -100.44 -100.00 TX Donley Beds Clarendon CLAR Middle Exell 35.38 -101.54 TX Moore Ogallala CLAR Middle Middle CLAR Ogallala Moore TX -101.54 35.38 Exell Quarry MacAdams Quarry Grant Ranch Quarries Rowe-Lewis General 35.06 - 35.04 -100.54 35.04 TX -100.54 Donley TX Donley Beds Clarendon Beds Clarendon MCLA Middle MCLA Middle Cormohipparion occidentale occidentale Cormohipparion Nannippus lenticularis lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus aztecus Nannippus aztecus Nannippus Nannippus lenticularis lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus lenticularis Nannippus Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion Genus Species Site Name Lat Long State Name Long Lat Site Genus Species Cormohipparion occidentale occidentale Cormohipparion occidentale Cormohipparion occidentale Cormohipparion

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Lubbock Lubbock Bridwell LLHP Late Brown Valentine LBAR Middle NE Hitchcock Valentine LBAR Middle 99.16 SD Charles Mix Fort Randall LBAR Middle Knox 97.40 NE Valentine LBAR Middle -99.16 SD Brule Randall -99.16 SD LBAR Middle Fort -100.24 -100.24 Cherry NE Hollow CLAR Ash Middle Channing 35.69 -102.47 TX Hartley BLANCAN Late Late Late BLANCAN BLANCAN Ballard Meade Hartley KS TX -100.40 42441) Formation (TMM Bridwell -102.47 Wallace Ranch Ranch Johnson's 33.40 Beck Ranch 2 KU Locality Rexriod -101.11 3 KU Locality Rexroad Angell Member TX ParkDeer Lubbock 37.28 Sanders Pit Gravel Seger 35.69 Channing 33.31 37.16 33.31 Cita Canyon 37.16 Bridwell -101.38 Quarry Meade's -100.46 -101.39 -100.46 Red Quarry 32.72 TX South Bijou Hill KS TX 37.41 -100.74 KS North Bijou Hill Meade Lubbock Quarry Burge ELHP -99.88 Meade TX Crooked Creek Locality 37.22 37.18 Scurry KS -100.48 -100.46 Late Bridwell Rexroad Meade 33.79 34.96 Quarry Bridge Crookston KS Rexroad KS A Railway Quarry -101.26 43.29 -101.89 Quarry Hottell Ranch Main 42.55 Meade 33.79 Meade 43.31 Hottell Ranch Horse Quarry - TX LLHP TX Journey Quarry -101.26 Immense BLANCAN Ballard 42.45 Hazard Homestead Quarry BLANCAN Crosby Randall Late 42.46 TX Quarry Jamber -100.49 Late Creek Crooked Late 41.32 Ballard Miller Creek -100.47 41.32 Crosby River Valley Niobrara NE -103.56 42.50 Wt-11 Penny Creek BLANCAN NE -103.56 BLANCAN 41.32 BLANCAN Blanco Cherry Sand Quarry East 40.03 Late NE -100.31 Late Late Cherry Quarry New Surface NE -103.56 -100.53 Quarry Echo BLANCAN Blanco Banner NE Quarry Echo Banner Late NE Quarry Humbug Cherry Valentine 42.54 Agate BLANCAN S of 23 mi. Banner 42.51 Valentine Joe's Quarry Late -100.29 40.01 42.49 Valentine -98.46 BLANCAN BLANCAN Valentine 42.09 42.09 -98.33 NE Late Late - ECLA Valentine NE Valentine LBAR -103.43 -103.43 Cherry NE Boyd LBAR 42.10 NE NE LBAR Middle Webster 42.10 42.10 Middle 42.10 LBAR Sioux -103.44 Sioux LBAR Middle -103.44 -103.44 Valentine -103.45 Middle NE 41.25 Valentine NE Middle Valentine NE NE Middle Sioux -104.46 Sioux Sioux Sioux Olcott Olcott LBAR WY LBAR ECLA Laramie Middle Olcott Olcott Olcott Middle Olcott Middle EBAR EBAR Early Early EBAR EBAR EBAR EBAR Early Early Early Early HEBA Early Norden Bridge Quarry Bridge Norden Quarry Top Carrot Welke Locality 42.47 -100.02 42.47 NE -100.04 42.46 Brown NE -100.06 Brown NE Valentine Valentine LBAR LBAR Middle Middle Nannippus aztecus aztecus Nannippus Genus Species Site Name Lat Long State County Formation Age Time Slice Nannippus aztecus aztecus Nannippus aztecus Nannippus beckensis Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus peninsulatus Nannippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus insignis Merychippus Merychippus insignis insignis Merychippus insignis Merychippus insignis Merychippus

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Ellis Ogallala EEHP Late EEHP Ellis Ogallala Beaver Ogallala MCLA Middle Decatur Group EEHP Ogallala Late KS Decatur Ogallala EEHP Late OK Roger Mills Ogallala Roger CLAR OK Middle OK Roger Mills Ogallala Roger CLAR OK Middle -101.00 -101.00 SD Bennett Beaver OK-100.15 Ogallala LLHP Late Middle -99.31 -99.31 Phillips KS Hollow EEHP Ash Late Mills Ogallala -99.38 Roger OK CLHE Middle Arnett 36.07 -99.57 OK -99.57 Quarry Beaver Creek Quarry Bear Arnett 36.07 Quarry Rosebud Agency Kat Quarry Trailside F. Sebastian Place Quarry Whisenhunt -99.57 Quarry MacAdams Anderson Quarry #2 42.53 43.13 Wild Horse Creek #1 36.45 -101.23 -100.49 -100.14 42.53 NE SD OK -100.15 Buis Ranch 39.48 36.45 Quarry Machaerodus Cherry Todd 35.04 -100.32 NE Kat Line Quarry 39.44 -100.02 35.47 Durham 35.51 -100.54 Cherry KS B Leptarctus -100.41 OK Jonas Wilson Quarry TX Beaver Ash Hollow Quarry Xmas Ash Hollow Connection Kat Quarry Donley Quarry 42.53 Hans Johnson Ash Hollow Kat Quarry CLAR -100.14 CLAR Quarry Leptarctus 36.55 Ogallala 42.53 Kat Quarry Line Quarter Beds Clarendon CLAR NE Kat Quarry Trailside 42.39 -100.15 Middle -100.14 Kat Quarry West Line Middle 42.53 Cherry MCLA -100.03 42.53 OK Burrows Above Pocket Mouse NE Middle 42.53 Quarry Xmas -100.15 MCLA 42.53 Beaver -100.15 NE Jonas Wilson Quarry Cherry -100.13 Middle 42.53 NE no. 11 Creek Soldier -100.14 Brown NE 42.00 42.53 no. 12 Creek Soldier Middle Ash Hollow -100.14 NE Cherry 42.53 Cherry NE 42.53 -98.00 42.53 -100.15 Ogallala Cherry NE Ash Hollow -100.15 Cherry -100.14 -100.14 CLAR NE NE Ash Hollow Cherry NE 42.39 NE Ash Hollow NE Cherry Antelope Ash Hollow 43.00 CLAR Cherry 42.53 Middle Cherry -100.03 Ash Hollow LLHP Cherry 43.00 Hollow Ash CLAR -100.00 -100.14 NE Hollow CLAR Ash -100.00 Middle CLAR Ash Hollow SD Ash Hollow Late NE CLAR Brown Middle SD CLAR Ash Hollow Ash Hollow Todd Ash Hollow Middle Cherry CLAR Middle Todd LCLAR Middle CLAR Middle CLAR CLAR Ash Hollow CLAR Middle Middle Middle Hollow Ash Middle Middle Middle CLAR CLAR Middle Middle Middle Middle Eubanks 40.52 -103.55 CO Weld Pawnee Creek LBAR Early Early LBAR Creek Pawnee Weld CO -103.55 -99.57 40.52 Eubanks Quarry fricki Amebelodon Olcott Quarry Long Island Quarry Quarry Kepler Clayton Quarry East Durham 35.51 40.23 Bushy Pine Butte Channel -100.15 NE 39.54 42.09 Frontier 43.00 42.41 -103.43 41.40 -99.55 -102.48 NE Ash Hollow NE Sioux NE Pit Kinkerman's Brown Morrill Pit Gravel Moundridge LEHP NE of Buis Ranch Locality 0.75 mi. Snake Creek 36.56 Late Ash Hollow Ash Hollow CLAR 38.12 CLAR 38.27 CLAR -97.31 Middle -97.28 Middle KS Middle KS McPherson McPherson Delmore Delmore EEHP EEHP Late Late Hipparion tehonense tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion tehonense Hipparion simpsoni Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion skinneri Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Genus insignis Merychippus forcei Hipparion forcei Hipparion tehonense Hipparion tehonense Hipparion Species tehonense Hipparion tehonense Hipparion tehonense Hipparion Site Name simpsoni Pseudhipparion Lat simpsoni Pseudhipparion simpsoni Pseudhipparion Long State County Formation Age Time Slice

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS h Hollow (maybe some Thin Valentine); some h Hollow (maybe Keya Paha Ash Hollow CLAR Middle Beaver Ogallala MCLA Middle NE Cherry NE Hollow CLAR Ash Middle -100.24 -100.24 Cherry NE Hollow CLAR Ash Middle r 43.16 -100.55 SD Todd Ash Hollow CLAR Middle CLAR Hollow Todd Ash SD -100.55 r 43.16 Bluejay Quarry 42.23 -98.06 NE Antelope Ash Hollow CLAR Middle Little Beaver B A Big Beaver Crooked Creek Locality 42.55 42.55 42.55 -100.24 -100.26 NE NE Cherry Cherry Ash Hollow Ash Hollow CLAR CLAR Middle Middle Soldier Creek no. no. 13 Creek Soldier no. 14 Creek Soldier no. 17 Creek Soldier Mound Spirit Rice Ranch Bear Quarry Hollow Horn Clayton Quarry East Quarry Cragin 43.00 Clayton Quarry 43.00 -100.00 Creek Quarry Bear 43.00 -100.00 1 no. Beads Creek 43.09 SD -100.00 V525 Creek Wolf SD V526 Creek Wolf -101.06 43.00 Todd SD V529 Creek Wolf 42.41 Todd V5324 SD Creek Wolf 43.00 -100.00 Todd V5325 Creek Wolf -99.55 Todd V5328 Creek Wolf -101.00 36.45 SD 42.53 42.41 V5329 Creek Wolf NE 43.00 SD V5330 Creek Wolf -100.21 Todd -101.23 -99.55 V5333 Creek Wolf Brown 43.00 Bennett -100.00 OK V5335 Creek Wolf 43.00 NE -102.24 Ash Hollow Canyon Big Spring NE 43.00 43.00 SD -102.24 Canyon Big Spring Cherry 43.00 Brown SD -102.24 11) (Site Canyon Big Spring Todd -102.24 43.00 Ash Hollow SD Fauna Mission CLAR -102.24 Shannon 43.01 SD SD -102.24 Shannon 42.59 Quarry Rosebud Agency SD -102.24 Shannon 43.00 Ash Hollow Canyon of Little White Rive Shannon CLAR SD Ash Hollow 43.07 -102.21 Middle 43.00 Shannon SD -102.27 43.07 Ash Hollow Shannon -101.56 SD -102.25 43.07 Ash Hollow Shannon Middle CLAR Middle SD -101.56 Ash Hollow CLAR Locality Upper County Road Shannon SD Ash Hollow Middle SD -101.56 43.13 CBig Beaver CLAR Shannon Ash Hollow Middle SD Bennett B Leptarctus CLAR 43.24 Shannon Ash Hollow SD Middle -100.49 Middle StadiumMcGinley's Bennett CLAR Ash Hollow CLAR -100.36 Quarry Jerry Bennett Middle Ash Hollow 42.54 SD CLAR Middle Precarious Quarry Middle Ash Hollow Middle CLAR SD -100.28 Middle Ash Hollow Todd Ash Hollow CLAR Middle Ash Hollow Mellette CLAR Middle Ash Hollow CLAR Middle CLAR Middle CLAR Middle 42.45 42.55 Middle CLAR Ash Hollow Middle 42.53 As CLAR -100.09 -100.27 Middle Middle 42.49 -100.15 42.45 NE Middle NE -100.03 CLAR Middle NE -100.10 Brown Cherry NE Cherry NE Middle Brown Ash Hollow Ash Hollow Ash Hollow CLAR Ash Hollow CLAR CLAR Middle Middle CLAR Middle Middle Pseudhipparion gratum gratum Pseudhipparion Pseudhipparion gratum gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Genus gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Species gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Site Name gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Lat gratum Pseudhipparion gratum Pseudhipparion Long gratum Pseudhipparion gratum Pseudhipparion Middle gratum Pseudhipparion State gratum Pseudhipparion County CLAR Elk gratum Pseudhipparion gratum Pseudhipparion Formation Age Time Slice gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion 130

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Cherry, Keya Paha, Boyd Keya Paha, Cherry, Ash Hollow CLAR Middle Middle ECLA Cherry Valentine ECLA Cherry Valentine Beaver Ogallala MCLA Middle Brown Hollow Ash CLAR Middle Donley Beds MCLA Middle Clarendon Donley Beds MCLA Middle Clarendon Cherry Valentine ECLA Middle OK Roger Mills Ogallala Roger CLAR OK Middle -101.07 TX Crosby Crosby TX -101.07 Crosby TX -101.07 Crosby TX -101.10 Couch Couch Couch MCLA Middle MCLA Middle MCLA Middle -100.06 NE Keya Paha Valentine -100.06 Keya NE Paha Valentine -100.03 Keya NE ECLA Middle ECLA Middle Exell 35.38 -101.54 TX Moore Ogallala CLAR Middle Middle CLAR Ogallala Moore TX -99.57 -101.54 School William's Quarry Whisenhunt Quarry Beaver Durham 35.51 35.38 Exell Coetas Creek Risley Ranch Charles Quarry MacAdams Quarry Grant 42.41 36.45 Beds Clarendon General 42433) (TMM Couch Formation Lower -99.55 -100.02 33.40 947) (TMM Couch Formation Upper 36.45 963) (TMM Couch Formation Upper OK NE 33.39 35.04 -100.14 Yoos Quarry 33.41 Beaver A Railway Quarry -100.52 35.28 35.04 35.04 OK Quarry Midway 2 no. Gregory -101.41 -100.54 TX -100.48 Butte Gap) Turtle (West 35.04 Quarry Burge TX TX Ogallala TX B Quarry Burge -100.54 Quarry Creek Gordon Potter Donley Crazy Locality TX 42.50 Lull Locality 39.42 43.04 Fence Line Locality Donley MCLA -100.31 42.53 Ranch Sherman Locality -100.50 Beds Clarendon -99.50 Ogallala 43.00 -100.14 NE Buzzard Feather Locality Middle KS 42.46 MCLA SD -99.00 Cherry NE 42.45 Beds Clarendon 42.44 Rawlins -100.39 Tripp Cherry -100.49 -100.49 SD Middle 42.49 MCLA CLAR 42.41 42.55 NE NE Gregory NE 42.48 42.54 -100.51 Valentine -100.23 Cherry Ogallala Middle Middle Cherry Cherry -100.27 Valentine NE Valentine NE NE Cherry LBAR Valentine CLAR Valentine Valentine ECLA ECLA Middle Middle Valentine ECLA Middle Middle ECLA ECLA Middle ECLA Middle Middle Middle Middle Kepler Quarry Kepler Cat Grasz Shore North Creek Lonergan Big Toad Beach Quarry Poison Ivy Quarry Chokecherry River Valley Niobrara 41.40 -102.48 41.16 41.17 41.16 41.17 42.25 NE 42.28 -101.48 42.54 -101.52 -101.48 -101.51 Morrill -98.09 -98.05 -100.29 NE NE NE NE NE Keith Keith NE NE Keith Keith Antelope Knox Ash Hollow Ash Hollow Ash Hollow Ash Hollow Ash Hollow CLAR Ash Hollow Ash Hollow CLAR Middle CLAR CLAR CLAR CLAR CLAR Middle Middle Middle Middle Middle Middle Sunrise Locality Wt-11 Penny Creek Wt-12 Penny Creek 42.55 40.01 -100.22 40.01 -98.33 -98.33 NE NE NE Webster Webster Valentine Valentine ECLA ECLA Middle Middle Middle Middle gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion hessei Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion Genus gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Species gratum Pseudhipparion gratum Pseudhipparion gratum Pseudhipparion Site Name Lat Long State County Formation Age Time Slice retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS llis Ogallala HMP Late HMP llis Ogallala Randall Goodnight Beds LLHP Late Late LLHP Late LLHP Beds Beds Goodnight Armstrong Randall Goodnight Ellis Ogallala LLHP Late Hemphill Beds ELHP Hemphill Late Wallace Ogallala ELHP Late TX Armstrong Goodnight Beds Beds Armstrong TX ELHP Goodnight Late 98.55 KS Smith Hollow 98.55 KS LEHP Late Ash -99.25 -99.25 Phillips KS Valentine BACL Middle 02 -99.32 -99.32 02 Ellis KS -99.32 02 Ellis KS -99.32 02 Group Ellis KS CLAR -99.32 02 Group Ellis KS CLAR Ogallala Middle Group CLAR Ogallala Middle Group CLAR Ogallala Middle Ogallala Middle 9a 39.00 -99.00 KS E KS -99.00 9a 39.00 Axtel 34.55 -101.42 TX Randall Goodnight Beds LLHP Late Late LLHP Late Late Beds LEHP ELHP Ogallala Ogallala Goodnight Ellis Texas Randall KS OK TX -99.30 -101.22 -101.42 PitsThe Quarry Edson Rhinoceros Hill Ganson Farm Bemis 38.52 36.45 Optima Gravel Pits Area Channing Coffee Ranch Quarry Fauna Goodnight General Axtel 34.55 39.09 39.07 Ranch Christian 42.11 Ranch Currie -101.30 38.26 -101.30 Ranch Smart -103.46 Gravel Quarry Strange C. J. KS 34.57 -97.28 KS 35.44 Ranch Long NE Sherman 35.41 -101.11 36.08 -100.31 KS Sioux -102.19 -99.57 McPherson TX 33.31 34.57 TX Ogallala -101.39 OK Hartley -101.29 35.02 Delmore Snake Creek TX 33.31 TX -101.45 Lubbock -101.38 ELHP 33.31 LEHP TX Ogallala EEHP TX -101.39 Late Bridwell Lubbock Late TX Late Lubbock LHMP Bridwell ELHP Late Bridwell Late LLHP LLHP Late Late Santee 42.49 -97.51 NE Knox Ash Hollow LLHP Late Late Late LLHP ELHP Hollow Hollow Ash Ash Knox Antelope NE NE -98.07 -97.51 - Quarry Lemoyne Ogallala Beach Feldt Ranch Honey Creek 42.23 Mailbox Santee 42.49 Devil's Nest Airstrip Reamsville 39.55 41.17 41.08 -101.53 -101.43 41.08 NE 42.41 42.49 NE Keith -101.40 -98.39 -97.43 Keith NE NE NE Keith Holt Ash Hollow Knox Ash Hollow EEHP Ash Hollow Ash Hollow EEHP Ash Hollow Late EEHP Late ELHP LLHP Late Late Late Optima 36.45 -101.22 OK Texas Ogallala ELHP Late Late ELHP Ogallala Texas OK Wt-13 Penny Creek June Quarry Quarry Lucht Quarry Verdigre -101.22 Devil's Gulch Horse Quarry Site Jones Canyon Creek Quarry Trail Quarry Escarpment 40.00 (LocalityHamburg 1) 42.42 (LocalityHamburg 2) -98.33 (LocalityHamburg 3) -99.47 (LocalityHamburg 8) 42.38 42.29 42.40 NE Republican River Beds (Phillips County) 39.59 -100.04 NE 42.42 36.45 Optima Webster -98.08 -99.46 41.25 Joseph R Thomasson Site 41.24 Brown -99.49 NE 39. -104.43 NE NE 39. -104.43 Brown 39. NE WY Knox Brown Valentine 39. WY Brown Laramie Valentine Laramie Valentine ECLA Valentine Valentine Ash Hollow Valentine LBAR Ash Hollow Middle ECLA ECLA BACL Middle LBAR BACL LBAR Middle Middle Middle Middle Middle Middle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion Genus retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion Species retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion Site Name retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion retrusum Pseudhipparion gidleyi Neohipparion eurystyle Neohipparion Lat Long State County Formation Age Time Slice

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Ellis Ogallala EEHP Late EEHP Ellis Ogallala Middle ECLA Cherry Valentine Hemphill Beds ELHP Hemphill Late TX Lipscomb TX Lipscomb Ogallala EEHP Late KS Decatur Ogallala EEHP Late -99.55 Ellis OK Ogallala EEHP Late Paha Valentine -100.06 Keya NE ECLA Middle Coffee Ranch Quarry Sebits Ranch General Box T Gallup Gulch Quarry Kepler Quarry Machaerodus Quarry Xmas 35.44 Kat Quarry East 36.05 Quarry Hans Johnson -100.31 Quarry Leptarctus -100.00 Kat Line Quarry TX Kat Quarry Line Quarter Kat Quarry 42.53 Trailside 42.49 Jack Swayze Quarry 41.40 -100.14 Quarry Arens 36.14 -101.44 42.53 1 Dawson no. -102.48 42.53 42.53 NE -100.05 2 Dawson no. NE -100.13 42.53 42.53 NE Butte Porcupine -100.14 Cherry -100.13 TX Quarry Poison Ivy Cherry -100.14 NE 42.53 Morrill -100.15 Gallup Gulch 42.53 NE NE Lipscomb Clayton Quarry 37.22 Cherry -100.14 NE NE -100.15 1 no. Beads Creek Cherry Cherry Canyon Big Spring -99.47 Ash Hollow Cherry NE Cherry Ash Hollow NE Quarry Burge Ogallala Ash Hollow 39.47 Quarry Creek Gordon Cherry KS 43.00 Cherry Ash Hollow Crazy Locality -99.54 43.00 CLAR Hollow Ash 43.18 Ash Hollow 42.25 Fence Line Locality Clark CLAR -100.00 CLAR Hollow Ash Ranch Sherman Locality Ash Hollow -100.00 -102.32 LEHP KS -98.09 SD CLAR 42.49 Middle Ash Hollow 42.41 43.00 CLAR Ash Hollow SD Middle CLAR SD Norton 43.07 Middle Todd NE CLAR -101.44 CLAR -99.55 42.46 -100.00 Late Todd Shannon Ogallala -101.56 Middle Antelope Middle CLAR Middle NE 42.45 -100.39 SD CLAR 42.49 NE Middle SD 42.55 Middle Cherry Ogallala 42.41 -100.49 Todd NE Brown Bennett -100.23 Ash Hollow Middle Ash Hollow Middle -100.51 EEHP Cherry NE NE NE Cherry Ash Hollow CLAR EEHP Cherry Late CLAR Ash Hollow Ash Hollow Valentine Middle Late CLAR Middle Valentine CLAR CLAR Valentine ECLA Middle Middle Middle ECLA Middle ECLA Middle Middle Middle Middle Middle Potter 41.06 -103.13 NE Cheyenne Ash Hollow LEHP Late Late Late LEHP LEHP Hollow Hollow Ash Ash Cheyenne Garden NE NE OK -102.23 -103.13 -99.57 42442) Formation (TMM Bridwell Pit 1Rentfro Anderson Quarry #2 33.40 Quarry Canyon Greenwood 41.20 Oshkosh -101.12 41.06 Potter Quarry fricki Amebelodon TX Quarry Minium 41.27 Lubbock Capps, George Neu, and Pratt Pitts Arnett 36.07 39.44 -103.03 36.05 35.52 -100.41 40.23 NE Bridwell -102.33 -100.15 Morrill TX NE 39.24 Hartley ELHP Frontier -100.08 Ash Hollow KS Late Ogallala Ash Hollow LEHP Graham LEHP Late ELHP Ash Hollow Late Late LEHP Late Fatigue Locality 42.43 -100.50 NE Cherry Valentine ECLA Middle Neohipparion leptode leptode Neohipparion leptode Neohipparion leptode Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion trampasense Neohipparion Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Genus eurystyle Neohipparion eurystyle Neohipparion eurystyle Neohipparion leptode Neohipparion leptode Neohipparion Species leptode Neohipparion leptode Neohipparion leptode Neohipparion Site Name leptode Neohipparion leptode Neohipparion Lat Long State County Formation Age Time Slice Neohipparion affine

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS onley Clarendon Beds MCLA Middle Middle MCLA Beds Clarendon onley Logan Logan Group LBAR Ogallala Middle Brown Brown Valentine Valentine LBAR LBAR Middle Middle NE Brown NE Valentine LBAR Middle NE Brown NE Valentine LBAR Middle Welke Locality Chance Locality Lost Norden Damsite Locality Quarry Penbrook Quarry Egelhoff Without a Quarry Name Quarry Bridge Crookston A Railway Quarry 42.47 42.46 Farm Myers 42.46 Quarry Hottell Ranch Main -100.01 -100.07 Hottell Ranch Horse Quarry -100.06 42.47 Journey Quarry Immense 42.51 42.46 NE 42.48 NE -100.02 -100.13 -100.47 Brown 41.32 -100.03 41.32 NE 42.50 NE NE -103.56 NE -103.56 Keya Paha 41.32 -100.31 Cherry Cherry NE 40.01 Valentine Keya Paha NE -103.56 NE Banner Valentine -98.32 Banner NE Cherry Valentine Valentine Valentine Banner NE LBAR Valentine Webster LBAR Valentine Valentine Middle LBAR LBAR LBAR Valentine Middle Valentine LBAR Middle Middle LBAR Middle LBAR LBAR Middle Middle Middle LBAR Middle Middle Kepler Quarry Kepler River Valley Niobrara Wt-11 Penny Creek Wt-12 Penny Creek Wt-13 Penny Creek Quarry Kilpatrick Site Hesperopithecus Olcott Hill 42.54 June Quarry Paleo Quarry 41.40 -100.29 40.01 Quarry Quinn Mastodon 40.01 1 and 2 Quinn Rhino Quarries -102.48 -98.33 NE 40.00 Quarry Leptarctus -98.33 NE Ash Pit Eli 42.10 Cherry 42.10 -98.33 NE 5 miles W of Rosebud Agency 4 or NE Morrill -103.43 -103.43 42.41 29) Wakeeney (KU Loc. Webster NE 42.41 Quarry MacAdams 43.13 Webster NE -99.55 NE Noble Ranch Webster 42.10 -99.55 Ash Hollow Quarry -100.56 Grant 42.38 Sioux Sioux 42.28 1 Quarry Rowe-Lewis NE Ash Hollow -103.43 Valentine -100.04 SD 42.53 NE 7 Quarry Rowe-Lewis -102.42 Valentine 39.05 Brown Sand Canyon (Colorado) CLAR NE Valentine Todd Brown NE -100.15 Yoos Quarry NE -99.45 CLAR Sioux Quarry Bridge Norden 42.53 Brown Snake Creek Snake Creek 35.04 NE ECLA Quarry Top Carrot Sheridan Middle ECLA KS Rosetta Stone Locality -101.27 Cherry -100.54 Ash Hollow 35.04 Middle ECLA Achilles Quarry Valentine 35.06 40.59 35.02 Trego CLAR Ash Hollow Middle CLAR NE TX -100.43 35.04 Middle Snake Creek Valentine Valentine -100.43 -103.28 -100.51 Middle Cherry CLAR Donley TX -100.54 42.47 Middle Middle Ash Hollow TX CLAR CO TX ECLA Donley -100.02 CLAR TX 42.46 Ogallala 39.42 42.47 Middle Donley D ECLA ECLA Donley NE -100.05 Middle Ash Hollow -100.50 CLAR Beds Clarendon -100.04 Middle Middle 42.47 Brown KS Middle NE Beds Clarendon Middle MCLA MCLA -100.04 Beds Clarendon Middle CLAR Brown Rawlins Beds Clarendon MCLA NE Middle MCLA Middle Valentine MCLA Middle Middle Ogallala Middle Valentine Middle LBAR CLAR LBAR Middle Middle Middle Merychippus republicanus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus Genus Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Species Neohipparion affine Neohipparion affine Neohipparion affine Site Name Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Neohipparion affine Lat Neohipparion affine Neohipparion affine Long Neohipparion affine Neohipparion affine republicanus Merychippus State republicanus Merychippus County republicanus Merychippus republicanus Merychippus Formation Age Time Slice

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Group Pawnee Creek/Ogallala LBAR Logan Logan Group LBAR Ogallala Middle NE Hitchcock Valentine LBAR Middle NE Boyd NE Valentine LBAR Middle -100.06 NE Keya Paha Valentine -100.06 Keya NE ECLA Middle -99.31 -99.31 Phillips KS Hollow EEHP Ash Late Annie's Geese Cross Hazard Homestead Quarry Quarry Jamber Forked Hills of Hayden II Vim-Peetz Creek Quarry Trail Ranch Sherman Locality 40.03 Quarry Quinn Mastodon 42.49 -100.53 Wt-11 Penny Creek Wt-12 Penny Creek -97.38 42.55 Wt-13 Penny Creek -99.01 Quarry Creek Gordon 42.51 NE 42.49 Fence Line Locality 41.25 42.41 -98.46 Quarry Burge Knox 40.59 West Valentine Quarry -104.43 -99.55 Quarry Boulder NE 40.01 -103.30 Sand Canyon (Colorado) WY 40.01 Boyd NE Pawnee Buttes -98.33 40.00 CO 42.46 Laramie Valentine -98.33 Brown Logan -98.33 42.55 -100.39 NE 42.50 NE -100.23 Webster NE NE 40.59 Ash Hollow Valentine -100.31 Webster 42.45 LBAR NE Cherry Webster Valentine -103.28 42.10 Group Ogallala NE -100.49 Cherry CO Valentine BACL Middle -103.43 Cherry 40.49 NE LBAR LBAR Valentine Valentine NE ECLA Valentine Cherry -103.58 Middle Sioux Middle Valentine Middle ECLA CO Valentine Middle ECLA Weld ECLA ECLA Valentine Middle ECLA Middle Olcott LBAR Middle Middle Middle ECLA Middle EBAR Middle Early Uhl Pit Quarry Xmas Kat QuarryWest Line Jack Swayze Quarry Long Island Quarry 42.53 37.22 -100.14 42.53 39.54 40.47 -99.47 NE -100.14 -103.56 Cherry NE KS CO Cherry Clark Weld Ash Hollow Hollow Ash Ogallala CLAR Ogallala Group CLAR LBAR Middle EEHP Middle Middle Late Wray 40.04 -102.13 CO Yuma Ogallala Group LEHP Late Late LEHP Group Ogallala Yuma CO -102.13 Quarry Leptarctus Kat Quarry East Box T Quarry fricki Amebelodon 40.04 Wray Quarry Lucht Quarry Kilpatrick 42.53 June Quarry Bear Quarry Hollow Horn 40.23 42.53 -100.15 Gallup Gulch -100.15 Clayton Quarry East -100.13 NE Clayton Quarry NE Creek Quarry Bear NE Cherry 36.14 43.09 Frontier Cherry 42.10 42.40 -100.05 -101.06 -103.43 -99.46 TX SD 42.38 Ash Hollow 42.41 Ash Hollow NE Lipscomb 42.49 NE Ash Hollow Todd -100.04 -99.55 Sioux 42.53 42.41 -101.44 Brown CLAR NE LEHP NE -101.23 -99.55 Ogallala (Hemphill Beds) CLAR NE Brown Brown NE Middle Ash Hollow NE Cherry Late Snake Creek Valentine Cherry Middle Brown LEHP Valentine CLAR Ash Hollow CLAR Ash Hollow ECLA Ash Hollow Ash Hollow Middle Middle CLAR ECLA CLAR Middle CLAR CLAR Middle Middle Middle Middle Middle Genus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus republicanus Merychippus Species coloradense Merychippus coloradense Merychippus coloradense Merychippus Site Name coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus coloradense Merychippus Lat Long State County Formation Age Time Slice Middle Middle coloradense Merychippus gidleyi Protohippus gidleyi Protohippus gidleyi Protohippus gidleyi Protohippus Protohippus gidleyi Protohippus gidleyi Protohippus gidleyi Protohippus Late gidleyi Protohippus gidleyi Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS own Valentine LBAR Middle LBAR own Valentine Cherry Valentine ECLA Middle ECLA Cherry Valentine Donley Donley Beds MCLA Middle Clarendon NE Hitchcock Valentine LBAR Middle NE Brown NE Valentine BACL Middle NE Cherry NE Hollow CLAR Ash Middle NE Boyd NE Valentine LBAR Middle -100.24 -100.24 Cherry NE Paha Hollow Valentine -100.03 Keya NE CLAR Ash Middle ECLA Middle r 43.16 -100.55 SD Todd Ash Hollow CLAR Middle CLAR Hollow Todd Ash SD -100.55 r 43.16 Elliott 42.36 -99.41 NE Br Fence Line Locality Fatigue Locality NE Little Beaver B Rim Locality North Crooked Creek Locality 42.55 -100.23 42.43 42.55 42.55 -99.41 42.55 NE -100.50 -100.27 -100.24 Cherry Quarry MacAdams NE Risley Ranch Adam NE NE Spoon Butte Cherry Cherry Wt-11 Penny Creek Cherry Wt-12 Penny Creek Valentine Hottell Ranch Horse Quarry Forked Hills of Hayden Valentine Falls Fairfield Ash Hollow 35.04 Elliott 42.36 Ash Hollow 35.03 ECLA Quarry Bridge Norden -100.54 41.32 Quarry Top Carrot -100.52 40.01 Rosetta Stone Locality ECLA CLAR TX -103.56 40.01 CLAR Middle 42.20 Quarry Bridge Crookston TX 42.55 -98.33 A Railway Quarry Donley -98.33 NE -104.04 Donley -99.01 Annie's Geese Cross Middle Middle NE Middle Hazard Homestead Quarry Banner 42.47 NE WY Quarry Jamber Webster 42.46 River Valley Niobrara Goshen -100.02 Webster 42.46 42.46 Beds Clarendon 42.47 Quarry Verdigre -100.06 Beds Clarendon NE -100.05 -100.47 Valentine -100.04 MCLA NE 40.03 MCLA Valentine 42.50 Brown 42.49 NE Valentine Ranch Beds Lay NE Brown -100.53 Middle -100.31 Cherry -97.38 Brown Middle LLAK 42.54 LBAR NE ECLA 42.51 NE -100.29 Valentine ECLA Cherry Valentine 42.29 Early -98.46 Middle Knox NE Valentine Middle Valentine -98.08 Middle Cherry NE LBAR NE LBAR Boyd Valentine LBAR Valentine LBAR Knox Middle Valentine Middle Middle Middle LBAR Valentine LBAR Valentine LBAR Middle Middle LBAR Middle LBAR Middle Middle Burge Quarry Burge B Quarry Burge Quarry Creek Gordon Crazy Locality 42.46 42.45 42.44 -100.39 -100.49 -100.49 42.41 NE NE NE -100.51 Cherry Cherry Cherry NE Valentine Valentine Valentine ECLA ECLA ECLA Middle Middle Middle Canyon of Little White Rive West Coon Creek Locality Buzzard Feather Locality Quarry Logan Bluejay Quarry Wt-11 Penny Creek Wt-12 Penny Creek 42.55 Quarry Midway 42.48 -100.28 Risley Ranch Charles 42.50 40.01 42.23 40.01 -100.02 -98.33 -98.06 35.04 -98.33 42.53 NE NE -100.52 NE -100.14 NE Keya Paha Webster TX Antelope Webster NE Cherry Valentine Valentine Ash Hollow Valentine LBAR Valentine CLAR ECLA ECLA Middle Middle Middle ECLA Middle Middle Protohippus supremus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus perditus Protohippus Protohippus supremus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus Genus supremus Protohippus Species Site Name supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus supremus Protohippus Lat Long State County Formation Age Time Slice

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APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS s Ogallala Group CLAR Middle CLAR Group s Ogallala Ogallala Group MCLA Middle MCLA Group Ogallala onley Clarendon Beds MCLA Middle Middle MCLA Beds Clarendon onley ogan Ogallala Group LBAR Middle Middle LBAR Group ogan Ogallala Beaver Ogallala MCLA Middle Logan Logan Group LBAR Ogallala Middle Donley Donley Beds MCLA Middle Clarendon Donley Beds MCLA Middle Clarendon CO Logan CO Group LBAR Middle Ogallala NE Boyd NE Valentine LBAR Middle 58 KS Rawlins KS 58 Ogallala CLHP Middle 100.42 TX Donley Donley TX 100.42 Beds MCLA Middle Clarendon -99.25 -99.25 Phillips KS Valentine BACL Middle General Vim-Peetz LocalityGeneral Vim-Peetz Fauna Mission Bear Quarry Hollow Horn Gallup Gulch Forked Hills of Hayden 40.59 Clayton Quarry East Clayton Quarry -103.31 43.09 -101.06 43.24 42.55 SD -100.36 -99.01 42.41 42.49 Todd SD -99.55 -101.44 42.41 Mellette NE NE -99.55 Ash Hollow Cherry Brown NE Ash Hollow Brown CLAR Ash Hollow Ash Hollow CLAR Middle Ash Hollow CLAR CLAR Middle CLAR Middle Middle Middle MacAdams Quarry MacAdams Quarry Grant Ranch Quarries Rowe-Lewis General Beds Clarendon General 35.06 Quarry Bridge Norden Quarry Top Carrot - Devil's Gulch Horse Quarry Sand Canyon (Colorado) 35.04 35.04 -100.54 42.47 -100.48 35.04 42.42 TX -100.02 -100.54 -99.47 TX 40.59 42.47 Donley NE TX -103.28 -100.04 NE Brown Donley CO NE Brown Beds Clarendon Brown MCLA Beds Clarendon Valentine Valentine Middle MCLA Valentine LBAR LBAR Middle LBAR Middle Middle Middle Exell 35.38 -101.54 TX Moore Ogallala CLAR Middle Middle CLAR Ogallala Ellis Moore KS TX -99.33 -101.54 Keller 39.04 Quarry Beaver 35.38 Exell Shannon Ranch Risley Ranch Charles 36.45 35.04 35.04 -100.14 -100.52 -100.54 OK TX TX D Gretna 39.50 -99.12 KS Phillip KS -99.12 June Quarry Devil's Gulch Horse Quarry Wt-11 Penny Creek Wt-12 Penny Creek Wt-13 Penny Creek Wt-15B Penny Creek 42.42 Gretna 39.50 -99.47 40.01 NE 42.38 40.01 -98.33 40.00 Brown -100.04 40.01 -98.33 -98.33 NE -98.32 NE NE Webster Brown NE NE Valentine Webster Webster Webster Valentine Valentine Valentine LBAR Valentine Valentine Middle ECLA ECLA ECLA ECLA ECLA Middle Middle Middle Middle Middle Devil's Gulch Horse Quarry County) (Rawlins Sappa Creek Republican River Beds (Phillips County) 39.59 A Railway Quarry Quarry Quinn Mastodon 39.42 42.42 Quarry Lucht Quarry Leptarctus -100. -99.47 Kennesaw I NE 42.41 Brown 42.50 -99.55 -100.31 42.53 NE 42.40 NE Valentine Brown -100.15 Cherry -99.46 40.59 NE NE -103.29 Cherry LBAR Valentine Brown CO Valentine L Middle Ash Hollow ECLA Valentine LBAR CLAR Middle Middle ECLA Middle Middle Calippus proplacidus proplacidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus Calippus regulus regulus Calippus regulus Calippus regulus Calippus regulus Calippus proplacidus Calippus proplacidus Calippus proplacidus Calippus proplacidus Calippus Calippus regulus regulus Calippus regulus Calippus regulus Calippus regulus Calippus regulus Calippus Calippus regulus regulus Calippus regulus Calippus regulus Calippus regulus Calippus regulus Calippus regulus Calippus regulus Calippus Genus perditus Protohippus perditus Protohippus perditus Protohippus regulus Calippus regulus Calippus Species regulus Calippus regulus Calippus regulus Calippus Site Name Lat Long State County Formation Age Time Slice

137

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS onley Clarendon Beds MCLA Middle Middle MCLA Beds Clarendon onley Donley Donley Beds MCLA Middle Clarendon Donley Beds MCLA Middle Clarendon NE Hitchcock Valentine LBAR Middle -100.24 -100.24 Cherry NE Hollow CLAR Ash Middle MacAdams Quarry MacAdams Quarry Grant Beds Clarendon General Quarry Machaerodus Quarry Hans Johnson Wade Quarry Quarry Xmas Connection Kat Quarry 35.04 35.04 Kat Quarry East Kat Quarry -100.54 -100.48 Quarry Leptarctus 42.53 35.04 42.53 Kat Quarry Line Quarter TX TX -100.14 Kat QuarryWest Line -100.54 -100.13 29) Wakeeney (KU Loc. Donley 42.53 NE Wade Quarry TX NE 42.43 Quarry Poison Ivy -100.15 Cherry 42.53 Quarry Lucht Donley Cherry -100.50 42.53 42.53 NE Little Beaver B -100.14 Beds Clarendon 42.53 2 Canyon No. Thief Horse NE -100.13 -100.14 42.53 Cherry 39.05 Bear Quarry Hollow Horn NE 42.53 -100.15 MCLA Gallup Gulch Cherry Ash Hollow NE -100.14 NE Beds Clarendon -99.45 Ash Hollow Cherry -100.14 NE Cherry Cherry NE Middle MCLA 42.25 KS NE 42.41 Ash Hollow Cherry 42.43 CLAR Cherry 43.09 CLAR Ash Hollow -98.09 Trego Cherry -99.58 -100.50 42.40 Middle Hollow Ash 42.55 -101.06 Middle Ash Hollow Hollow CLAR Ash NE NE NE -99.46 Middle -100.24 SD Ash Hollow CLAR Ash Hollow Antelope Brown Cherry CLAR Ash Hollow 42.49 Ogallala NE NE Todd Middle CLAR CLAR Middle -101.44 Cherry Brown CLAR Middle CLAR Ash Hollow CLAR Middle NE Middle Ash Hollow Ash Hollow MCLA Middle Ash Hollow Cherry Middle Middle Ash Hollow Valentine CLAR CLAR CLAR Middle CLAR Middle CLAR Ash Hollow Middle Middle ECLA Middle Middle CLAR Middle Middle Exell 35.38 -101.54 TX Moore Ogallala CLAR Middle Middle CLAR Ogallala Moore TX Creek Quarry Bear Oak Creek Little Beaver B Crooked Creek Locality A Railway Quarry -101.54 Farm Myers Hottell Ranch Horse Quarry Quarry Poison Ivy 42.53 Quarry Chokecherry 42.55 Annie's Geese Cross -101.23 Hazard Homestead Quarry 41.32 42.55 Quarry Jamber NE 43.18 42.50 River Valley Niobrara -103.56 -100.24 Quarry Verdigre Cherry -100.26 -100.31 Ainsworth Near NE NE 42.25 35.38 Exell 40.01 40.03 42.28 SD NE Shannon Ranch Banner 42.49 Cherry -98.09 -98.32 -100.53 -98.05 Risley Ranch Charles Todd Cherry Ash Hollow -97.38 42.54 NE NE NE 42.51 NE -100.29 Valentine Antelope Webster Knox Ash Hollow CLAR 42.29 -98.46 Valentine Knox Oak Creek? NE 42.33 -98.08 35.04 Cherry NE Middle -99.51 CLAR Ash Hollow 35.04 LBAR Valentine -100.52 NE CLAR Boyd Ash Hollow LBAR -100.54 NE Valentine Knox TX Middle Middle CLAR TX Brown Valentine Middle Middle LBAR CLAR D Valentine Middle LBAR Middle Valentine Middle LBAR Hollow Ash Middle LBAR Middle CLAR LBAR Middle Middle Middle Calippus placidus placidus Calippus placidus Calippus placidus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus cerasinus Calippus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus Genus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus Species placidus Calippus placidus Calippus placidus Calippus Site Name placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus placidus Calippus Lat Long State County Formation Age Time Slice

138

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS

Ellis Ogallala EEHP Late EEHP Ellis Ogallala Beaver Beaver Ogallala Ogallala MCLA MCLA Middle Middle Donley Donley Beds MCLA Middle Clarendon 100.42 TX Donley Donley TX 100.42 Beds MCLA Middle Clarendon -99.38 OK Roger Mills Ogallala -99.38 Roger OK CLHE Middle -99.31 Phillips KS -99.55 Hollow Ellis OK EEHP Ash Late Ogallala EEHP Late MacAdams Quarry MacAdams Quarry Grant Ranch Quarries Rowe-Lewis General Wild Horse Creek #1 35.06 - 35.04 -100.54 35.47 35.04 TX -100.54 Donley TX Donley Beds Clarendon MCLA Beds Clarendon Middle MCLA Middle Eubanks 40.52 -103.55 CO Weld Pawnee Creek LBAR Early Early LBAR Late Creek LEHP Hollow Pawnee Weld Ash Clayton Quarry East 3 Dawson no. Clayton Quarry Quarry Chokecherry Garden Creek Quarry Bear CO V5324 Creek Wolf V5329 Creek Wolf V5335 Creek Wolf 42.41 Canyon Big Spring Fauna Mission -99.55 Quarry Whisenhunt 42.28 43.00 42.41 Quarry Beaver NE 42.53 -98.05 Quarry Cragin -100.00 -99.55 43.00 Risley Ranch Charles Brown NE -103.55 -101.23 43.01 SD NE -102.24 43.00 NE NE -102.24 43.07 Todd Knox SD -102.25 Brown Cherry SD -101.56 36.45 Ash Hollow Sand Quarry East OK 43.24 Shannon SD Quarry Echo Shannon -100.02 SD 35.04 -100.36 Mill Quarry 36.45 Shannon and Mastodon Quarry Horse Bennett Ash Hollow OK 36.45 CLAR Ash Hollow -100.52 Ash Hollow SD -100.14 of Kremmling 5 miles E Ash Hollow -102.23 Beaver 40.52 Eubanks -100.21 Ash Hollow TX Mellette OK Pawnee Buttes Ash Hollow Middle CLAR CLAR OK General Keota Fauna CLAR Ash Hollow 40.49 CLAR the Road Quarry of Middle 42.09 CLAR Foley Quarry -104.04 Ogallala CLAR Middle -99.57 Ash Hollow 40.03 Middle Quarry Greenside -103.43 Middle Middle 42.10 Quarry CLAR Thomson CO -106.16 Middle NE Draw Merychippus 42.11 -103.44 Middle Weld 42.24 Red Valley Member General CLAR Sioux CO -103.44 41.20 40.49 Oshkosh Middle MCLA NE -103.02 Quarry Lemoyne 40.49 Grand Middle -104.04 NE Ogallala Beach Sioux Middle NE -103.58 Feldt Ranch Middle 42.24 Sioux CO Long Island Quarry Pawnee Creek 42.10 Box Butte 42.24 Olcott CO Capps, George Neu, and Pratt Pitts -103.01 42.10 Weld 42.11 -103.44 Arnett 36.07 Troublesome -103.02 Weld LBAR NE -103.45 Olcott 36.05 -103.47 NE Box Butte NE Olcott Box Butte/Dawes NE NE 41.17 HEBA Sioux Box Butte Middle Box Butte EBAR Pawnee Creek Sioux 41.08 Sioux -101.53 39.54 Pawnee Creek LHMF Early -101.43 EBAR 41.08 NE Early LBAR Box Butte LHMF EBAR LBAR Sheep Creek NE Keith -101.40 Early Sheep Creek Early Sheep Creek Middle Keith NE Early Early Middle LHMF LHMF Keith LHMF LHMF Ash Hollow Early Early Ash Hollow Early Early EEHP Ash Hollow EEHP Late EEHP Late Late Calippus martini Calippus martini Calippus martini Calippus martini Calippus Genus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus Species martini Calippus martini Calippus martini Calippus Site Name martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus martini Calippus intermontanus Merychippus Lat intermontanus Merychippus intermontanus Merychippus Long sejunctus Merychippus sejunctus Merychippus sejunctus Merychippus State sejunctus Merychippus County sejunctus Merychippus isonesus Acritohippus isonesus Acritohippus tertius Acritohippus Formation Age Time Slice tertius Acritohippus tertius Acritohippus tertius Acritohippus nobilis Pliohippus nobilis Pliohippus nobilis Pliohippus nobilis Pliohippus nobilis Pliohippus nobilis Pliohippus nobilis Pliohippus 139

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Donley Donley Beds MCLA Clarendon Middle TX Lipscomb TX Ogallala EEHP Late TX Lipscomb TX Ogallala EEHp Late OK Roger Mills ECLA/EHEMPH Middle -101.07 TX Crosby Crosby TX -101.07 Crosby TX -101.09 Crosby TX -101.07 Couch Crosby TX -101.10 Couch Crosby TX -101.10 Couch Couch MCLA Couch MCLA MCLA Middle MCLA Middle MCLA Middle Middle Middle Sebits Ranch Locality 24-A 36.05 -100.00 Sebits Ranch Locality 24-B 36.05 -100.00 Box T Box T V526 Creek Wolf V527 Creek Wolf V529 Creek Wolf V5324 Creek Wolf V5325 Creek Wolf V5326 Creek Wolf V5328 Creek Wolf V5332 Creek Wolf 43.00 Butte Gap) Turtle (West 43.00 Canyon Big Spring -102.24 43.00 Canyon Big Spring 43.00 -102.23 36.14 Canyon Big Spring SD 43.00 -102.24 -102.24 Canyon Big Spring SD 42.59 -100.05 Shannon -102.24 Canyon Big Spring SD 43.00 43.04 SD Shannon -102.23 Oak Creek TX 43.00 SD Shannon -102.24 StadiumMcGinley's -99.50 Shannon NE Lipscomb -102.27 Quarry Serendipity 43.07 Shannon SD Ash Hollow Bluejay Quarry 43.07 SD Sheridan SD Ash Hollow -101.56 Quarry Kepler 43.07 Shannon Ash Hollow -101.56 Shore North 43.07 Tripp Ogallala Ash Hollow Shannon SD -101.56 Creek Lonergan CLAR 43.07 Ash Hollow SD -101.56 Middle Quarry Poison Ivy CLAR Ash Hollow Bennett SD 42.45 -101.56 Middle Quarry Chokecherry CLAR Ash Hollow Bennett CLAR SD Middle Risley Ranch Charles 42.49 Ash Hollow Bennett -100.09 Middle LEHP CLAR SD 43.18 Valentine Middle Bennett CLAR -100.04 Middle NE Bennett 42.23 Ash Hollow CLAR -100.26 Ash Hollow CLAR NE 41.40 Brown -98.06 SD Ash Hollow 41.16 ECLA Late Keya Paha 42.25 -102.48 41.16 Ash Hollow 42.28 CLAR 35.04 Todd NE Ash Hollow -101.48 CLAR -98.09 -101.48 Middle NE -98.05 CLAR -100.52 Antelope Middle Ash Hollow Ash Hollow NE CLAR Morrill NE NE NE Middle TX CLAR Keith Middle Keith Antelope Knox Oak Creek? Middle CLAR Ash Hollow CLAR Middle Ash Hollow Middle Middle CLAR Ash Hollow CLAR Ash Hollow Ash Hollow Ash Hollow Middle Middle CLAR CLAR CLAR CLAR Middle CLAR Middle Middle Middle Middle Middle Middle Durham 35.00 -99.00 42443) (TMM Couch Formation Lower 33.41 947) (TMM Couch Formation Upper 963) (TMM Couch Formation Upper 33.39 42448) (TMM Couch Formation Upper 33.41 33.41 Durham 35.00 Grant Quarry Quarry Grant 42433) (TMM Couch Formation Lower 33.40 35.04 -100.54 TX Donley Beds Clarendon MCLA Middle Genus nobilis Pliohippus Species Site Name Lat Long State County Formation Age Time Slice Pliohippus nobilis nobilis Pliohippus Pliohippus nobilis nobilis Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus Pliohippus pernix Pliohippus pernix Pliohippus 140

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Clarendon Beds MCLA Middle MCLA Beds Clarendon Group Pawnee Creek/Ogallala LBAR Cherry, Keya Paha, Boyd Keya Paha, Cherry, Late Valentine LLHP Late LLHP LBAR Beds Beds Goodnight Armstrong Randall Goodnight Ellis Ogallala LLHP Late Logan Logan Group LBAR Ogallala Middle NE Hitchcock Valentine LBAR Middle CO Logan CO Group LBAR Middle Ogallala NE Boyd NE Valentine LBAR Middle 43 TX Donley Donley TX 43 Beds MCLA Middle Clarendon Pawnee Buttes 40.49 -103.58 CO Weld Axtel 34.55 -101.42 TX Randall Goodnight Beds LLHP Late Late LLHP Late Beds LEHP Hollow Goodnight Randall Ash Garden TX NE -101.42 Devil's Gulch Horse Quarry Sand Canyon (Colorado) and Mastodon Quarry Horse 42.42 LocalityGeneral Vim-Peetz -102.23 Forked Hills of Hayden -99.47 40.59 Nenzel Quarry Gravel Pits -103.28 40.49 NE Axtel 34.55 40.59 Ranch Christian -104.04 CO Brown Ranch Currie -103.31 Pit 1Rentfro 42.55 CO Ranch Smart Weld -99.01 Pit 1Rentfro 41.20 Oshkosh Valentine Quarry Edson 42.48 Quarry Lost -101.08 36.08 34.57 Pawnee Creek LBAR NE -99.57 -101.29 35.02 Cherry 35.52 LBAR TX -101.45 OK Middle 33.31 -102.33 35.52 TX -101.38 Middle 39.09 TX -102.33 Valentine TX 38.47 -101.30 Hartley TX Lubbock -101.29 KS Hartley LBAR KS Sherman Ogallala Bridwell Wallace Middle Ogallala Ogallala ELHP Ogallala LLHP ELHP Late ELHP Late ELHP Late Late Late Exell 35.38 -101.54 TX Moore Ogallala CLAR Middle Middle CLAR Ogallala Moore Donley TX TX -101.54 no. 6 Creek Soldier -100.52 no. 10 Creek Soldier no. 17 Creek Soldier Mound Spirit Creek Quarry Bear Quarry Burge Quarry Kilpatrick Little Beaver B 43.00 Quarry Midway 43.00 35.38 Exell 43.00 -100.00 -100.00 Quarry MacAdams -100.00 Dilli 35.04 SD 42.53 SD skull site fossulatus 1938 Pliohippus 43.00 SD A Railway Quarry Todd -101.23 Todd 35.10 Hottell Ranch Horse Quarry 42.10 -100.00 42.45 Todd Hazard Homestead Quarry NE -100. -103.43 42.55 River Valley Niobrara -100.49 SD 42.53 Cherry 35.04 -100.24 NE Todd NE -100.14 41.32 -100.54 Sioux NE Cherry 40.03 -103.56 NE 42.50 TX Cherry Ash Hollow -100.53 Cherry NE 42.54 -100.31 Donley Banner -100.29 Valentine Snake Creek NE CLAR Ash Hollow NE Cherry Valentine Beds Clarendon CLAR Middle Valentine ECLA CLAR MCLA Middle Middle Valentine ECLA Middle Middle Middle Middle Middle LBAR Middle LBAR Middle Middle Middle Pliohippus mirabilis Pliohippus Middle Middle mirabilis Pliohippus mirabilis Pliohippus Middle mirabilis Pliohippus mirabilis Pliohippus mirabilis Pliohippus mirabilis Pliohippus stockii Astrohippus stockii Astrohippus stockii Astrohippus stockii Astrohippus stockii Astrohippus stockii Astrohippus stockii Astrohippus ansae Astrohippus ansae Astrohippus ansae Astrohippus Genus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus pernix Pliohippus Species pernix Pliohippus pernix Pliohippus pernix Pliohippus Site Name pernix Pliohippus fossulatus Pliohippus fossulatus Pliohippus fossulatus Pliohippus fossulatus Pliohippus mirabilis Pliohippus mirabilis Pliohippus mirabilis Pliohippus mirabilis Pliohippus Lat Long State County Formation Age Time Slice 141

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Randall Goodnight Beds LLHP Late Late LLHP Late LLHP Beds Beds Goodnight Armstrong Randall Goodnight Late Wallace Ogallala ELHP Hemphill Beds ELHP Hemphill Late Hemphill Beds ELHP Hemphill Late Lubbock Lubbock Bridwell LLHP Late Hemphill Beds ELHP Hemphill Late Wallace Ogallala ELHP Late TX Armstrong Goodnight Beds Beds Armstrong TX ELHP Goodnight Late TX Armstrong Goodnight Beds Beds Armstrong TX ELHP Goodnight Late 39 TX Lubbock Lubbock TX 39 Bridwell LLHP Late Mailbox 42.23 -98.07 NE Antelope Ash Hollow ELHP Late Late ELHP Late Hollow Late LEHP ELHP Ash Ogallala Group Antelope Texas NE Ogallala OK -98.07 Yuma Ranch Currie -101.22 Quarry Uptegrove Honey Creek 42.23 Mailbox Quarry fricki Amebelodon Aphelops Quarries CO Aphelops Quarries PitsThe Draw Pliohippus 41.15 Coffee Ranch Quarry 40.23 35.02 36.45 Optima -102.54 -100.15 Quarry Edson -101.45 42.41 Quarry Edson NE 42.12 NE Quarry Lost TX -98.39 42.12 Found Quarry Cheyenne Frontier -103.47 Rhinoceros Hill -102.13 -103.47 NE 35.44 Ranch Parcell 42.11 NE Coffee Ranch Quarry NE Holt -100.31 Fauna Goodnight General Ash Hollow -103.46 Sioux 42.11 Ash Hollow Gravel Quarry Strange C. J. Sioux TX Gravel Quarry Strange C. J. NE -103.46 39.09 Ranch Long 39.09 ELHP Sioux Ranch Long NE -101.30 LEHP 42441) Formation (TMM Bridwell Ash Hollow 38.47 -101.30 Snake Creek 34.57 38.47 33.31 39.07 Sioux 35.44 Ranch Johnson's KS Snake Creek 33.31 Late -101.29 Pit 1Rentfro -101.11 KS -101.29 33.40 35.59 -101.39 Late -101.30 -100.31 Sherman 40.04 Wray -101.39 ELHP LEHP KS Snake Creek Sherman of McLean NE 10 mi. KS -101.11 -100.35 TX KS LEHP TX Quarry Greenside TX Wallace Snake Creek Quarry Thomson TX Lubbock TX Late Late Ogallala Lubbock ELHP Late Lubbock Roberts Ogallala 33.31 33.31 LEHP 33.31 Ogallala -101.39 Bridwell Late 35.21 -101.39 Bridwell -101.39 ELHP TX Bridwell 35.52 Ogallala Late -100.33 ELHP TX 42.10 TX Lubbock -102.33 42.10 TX Lubbock ELHP ELHP Late -103.44 Lubbock TX ELHP Late -103.45 Gray ELHP NE ELHP Hartley Bridwell Late Late NE Bridwell Sioux Late Bridwell Late Sioux Late Ogallala? Ogallala LLHP LLHP Sheep Creek LLHP Sheep Creek Late HEMP Late ELHP Late LHMF LHMF Late Late Early Early Axtel 34.55 -101.42 TX Randall Goodnight Beds LLHP Late Late LLHP Beds Goodnight Randall TX -101.42 Pits Parker V. V. Axtel 34.55 Ranch Christian 36.15 -100.02 34.57 TX -101.29 Lipscomb TX Ogallala EEHP Late Johnson's Ranch Ranch Johnson's Ranch Johnson's West of 33.31 -101. 33.31 -101.39 TX Lubbock Bridwell LLHP Late General Goodnight Fauna Goodnight General Ranch Smart Gravel Quarry Strange C. J. Wallace Ranch 34.57 33.31 -101.11 -101.39 TX 33.31 33.31 Lubbock -101.38 -101.38 TX TX Bridwell Lubbock Bridwell ELHP Late LLHP Late Coffee Ranch Quarry 35.44 -100.31 TX Dinohippus mexicanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus leidyanus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus interpolatus Dinohippus primus Merychippus primus Merychippus Hippidion Hippidion mexicanus Dinohippus mexicanus Dinohippus Astrohippus ansae ansae Astrohippus ansae Astrohippus Astrohippus ansae ansae Astrohippus ansae Astrohippus ansae Astrohippus ansae Astrohippus Genus ansae Astrohippus Species Site Name Lat Long State County Formation Age Time Slice 142

APPENDIX C: SPECIES OCCURRENCE DATA FOR THE GREAT PLAINS Sioux Sheep Creek LHMF Early LHMF Creek Sheep Sioux Natrona Rock Split LHMF Early WY Natrona Rock Split LHMF Early -97.79 KS Republc Republc KS -97.79 Late BLANCAN 42.26 -107.26 -107.26 42.26 WY Sanders 37.28 -100.40 KS Meade Ballard BLANCAN Late Late Late BLANCAN Ballard BLANCAN Meade KS Hartley -100.40 Quarry Creek Cottonwood TX Mountain Cross Donnelly Ranch Angell Member ParkDeer 37.28 Sanders 42.32 Pit Gravel Seger -103.08 Loc. White Rock Wilson Loc. White Rock Hibbard NE Loc. White Rock Middle 40.26 -102.48 White Rock Hanel Sandpit Loc Dawes 37.16 Loc White Rock Railroad -108.17 37.41 White Rock Millen Sandpit Loc. -103.51 39.91 A Locality Broadwater 39.91 CO 39.88 -99.88 Lisco Locality C CO -97.87 37.22 39.91 37.18 9 Quarry Meade's 0.00 Moffat -97.87 Runningwater -97.53 KS Quarry Marmot Animas Las -100.48 39.84 -97.87 -100.46 KS Quarry Carter KS KS Meade Cita Canyon EHMF -97.53 KS KS Republc KS 35.68 Channing Republc 41.60 Republc Park Browns DumpHereford Meade Meade KS Republc Beck Ranch Early -102.74 Ranch (Lower) Martin Republc Ballard 41.52 HMF NE 33.78 -102.53 Creek Crooked Morrill 33.79 Ballard -101.26 NE BLANCAN 33.78 Early -101.26 TX BLANCAN BLANCAN Late 34.96 Garden -101.26 Late 34.51 TX Crosby Late 34.85 -101.89 BLANCAN TX BLANCAN Crosby -101.43 -102.34 BLANCAN BLANCAN 32.72 Late Late TX Crosby Late BLANCAN TX Late TX -100.74 Blanco Randall Late Briscoe BLANCAN Deaf Smith TX Blanco Late Blanco Scurry BLANCAN Late BLANCAN Tule Late BLANCAN BLANCAN Late Late BLANCAN Late IRV BLANCAN BLANCAN Late Late Late BLANCAN Late Thistle Quarry Quarry Thistle Stonehouse Draw Agate S of 23 mi. Foley Quarry D Creek Prospect Dry Red Valley Member General Quarry Companion Split Rock, UCMP V-77151 Devil's Gate (UCMP V-77155) 42.10 42.10 42.24 42.10 42.24 -103.45 -103.44 -103.01 42.27 -103.45 -103.01 42.24 NE NE NE -107.32 42.08 NE NE -103.02 Sioux Sioux Box Butte/Dawes -103.49 Sioux Box Butte Box Butte NE NE Box Butte Sioux Sheep Creek Box Butte Sheep Creek LHMF Sheep Creek Box Butte Early LHMF LHMF LHMF LHMF Sheep Creek LHMF Early Early Early Early LHMF Early Early Hilltop Quarry 42.10 -103.44 NE Parahippus leonensis leonensis Parahippus leonensis Parahippus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus simplicidens Equus Merychippus primus primus Merychippus primus Merychippus primus Merychippus primus Merychippus primus Merychippus primus Merychippus primus Merychippus primus Merychippus primus Merychippus Genus primus Merychippus Species Site Name Lat Long State County Formation Age Time Slice

143

APPENDIX D: ORIGINAL ENVIRONMENTAL DATA

Geographic location information for each environmental data point with the original value of the environmental variable and reference. The age and NALMA for each site is included.

Appendix D1: Stable Isotopes

AppendixD2: Mean Annual Percipitation (MAP)

AppendixD3: Mollic Horizon

AppendixD4: Vegetation

AppendixD5: Crocodile Presence/Absense 144

APPENDIX D1: STABLE ISOTOPES

% Location Name Latitude Longitude Age Time Slice NALMA δ13C Reference C4 Fox and Koch Breakneck Hill 41.60 -102.80 23.00 Early Arikareean -7.20* 20 2003 Reference section 1 Fox and Koch (Fox and Koch, 42.40 -103.10 17.50 Early Hemingfordian -7.54* 18 2003 2003) Refence section 2 Fox and Koch (Fox and Koch, 42.40 -103.30 17.50 Early Hemingfordian -6.95* 21 2003 2003)

Wang et al. 1994; Damuth Echo Quarry 42.10 -103.44 15.00 Early Barstovian -8.50† 17 et al. 2002; Passey et al. 2002

Wang et al. West Surface Quarry 42.09 -103.43 15.00 Early Barstovian -8.50† 17 1994; Passey et al. 2002 Damuth et al. Thompson Quarry 42.19 -103.75 17.50 Early Hemingfordian -9.15† 14 2002; Passey et al. 2002 East Sand Quarry 42.16 -103.73 15.50 Early Barstovian -7.00† 27 Clouthier 1994

Long Quarry 42.19 -103.73 18.00 Early Hemingfordian 0† 0 Clouthier 1994

Cottonwood Creek 42.55 -103.14 18.50 Early Hemingfordian 0† 0 Clouthier 1994 Quarry Wang et al. Brown County 42.47 -99.94 3.30 Early Hemingfordian -7.80† 31 1994 Wang et al. Hill Top Quarry 42.10 -103.44 17.00 Early Hemingfordian -9.90† 9 1994 Wang et al. Thomson Quarry 42.10 -103.45 17.50 Early Hemingfordian -10.60† 4 1994 Damuth et al. Norden Bridge 42.80 -100.00 14.30 Middle Barstovian -6.60* 25 2002; Fox and Quarry Koch 2003 Norden Bridge Passey et al. 42.80 -100.00 14.30 Middle Barstovian -8.93† 17 Quarry 2002 Fox and Koch Egelhoff Quarry 42.80 -100.10 14.30 Middle Barstovian -6.05* 28 2003 Ashfall Fossil Beds Fox and Koch State Historical Park 42.40 -98.20 13.70 Middle Barstovian -8.63* 12 2003 A Ashfall Fossil Beds Fox and Koch State Historical Park 42.20 -98.20 13.70 Middle Barstovian -8.00* 15 2003 B Yellowhouse Fox and Koch 33.50 -101.60 13.05 Middle Barstovian -5.99* 29 Canyon A1 2003 Yellowhouse Fox and Koch 33.50 -101.60 13.05 Middle Barstovian -5.82* 30 Canyon B1 2003 145

Ashfall Fossil Beds Fox and Koch State Historical Park 42.20 -98.20 12.70 Middle Barstovian -7.00* 21 2003 C 146

APPENDIX D1: STABLE ISOTOPES

Fox and Koch PE Pit 36.10 -100.00 9.60 Middle Clarendonian -7.37* 19 2003 Thomasson Minimum Quarry 39.40 -100.10 9.55 Middle Clarendonian -6.98* 21 1991; Fox and Koch 2003 Fox and Koch Greenwood Canyon 41.50 -103.10 9.10 Middle Clarendonian -6.80* 22 2003 Fox and Koch Box T 36.20 -100.10 8.75 Middle Clarendonian -7.50* 18 2003 Fox and Koch Higgins locality 36.10 -100.00 8.75 Middle Clarendonian -7.10* 20 2003 Fox and Koch Wildohorse Canyon 41.30 -102.40 8.65 Middle Clarendonian -6.28* 28 2003 Fox and Fisher Cole Highway Pit 36.04 -100.01 9.50 Middle Clarendonian -9.60† 13 2004 Rock Ledge Fox and Fisher 42.73 -99.88 10.00 Middle Clarendonian -8.80† 18 Mastodon Quarry 2004 Megabelodon Fox and Fisher 42.43 -100.50 11.00 Middle Clarendonian -10.40† 4 Quarry 2004 Damuth et al. Myers Farm 40.10 -98.47 12.00 Middle Barstovian -13.00† 0 2002; Fox and Fisher 2004 Fox and Fisher George Elliott Place 42.71 -99.79 12.00 Middle Barstovian -9.50† 13 2004 Fox and Fisher Hottell Ranch 41.32 -103.56 14.00 Middle Barstovian -8.80† 15 2004 Wang et al. Burge Quarry A 42.74 -100.42 11.00 Middle Clarendonian -9.50† 13 1994; Fox and Fisher 2004 Fox and Fisher Ewert Quarry 42.83 -101.17 11.00 Middle Clarendonian -9.20† 15 2004 Devil's Gulch Fox and Fisher 42.71 -99.79 13.70 Middle Barstovian -8.60† 19 Quarry 2004 Passey et al. North Shore 41.16 -101.48 9.00 Middle Clarendonian -9.05† 16 2002 Passey et al. Pratt Slide 42.37 -100.03 9.00 Middle Clarendonian -10.92† 4 2002 Wang et al. Xmas Quarry 42.53 -100.14 9.00 Middle Clarendonian -10.90† 4 1994; Passey et al. 2002 Passey et al. Zochol Quarry 42.00 -103.00 10.00 Middle Clarendonian -9.15† 16 2002 Passey et al. Annie's Geese Cross 42.49 -97.38 12.00 Middle Barstovian -9.60† 13 2002 Passey et al. Hazard Homestead 40.03 -100.53 12.00 Middle Barstovian -8.10† 23 2002 Passey et al. A&C Risley Farm 35.04 -100.52 10.50 Middle Clarendonian -11.00† 3 2002 Passey et al. Couch Ranch 36.00 -101.00 10.50 Middle Clarendonian -9.70† 12 2002 147

APPENDIX D1: STABLE ISOTOPES

Passey et al. Stanton Ranch 35.02 -100.49 10.50 Middle Clarendonian -11.30† 1 2002 Passey et al. MacAdams Quarry 35.04 -100.54 11.00 Middle Clarendonian -10.68† 5 2002

Clayton Quarry 42.69 -99.92 10.00 Middle Clarendonian -9.45† 14 Clouthier 1994

Burge Quarry B 42.74 -100.42 12.00 Middle Barstovian -11.50† 0 Clouthier 1994 Fox and Koch Kimball 41.20 -103.70 7.25 Late Hemphillian -5.57* 32 2003 Fox and Koch Breakneck Hill 41.60 -102.80 7.25 Late Hemphillian -7.20* 20 2003

Lake McConnaughy Fox and Koch 41.20 -101.70 7.25 Late Hemphillian -7.02* 21 Dam 2003

Lake McConnaughy Passey et al. 41.20 -101.70 7.25 Late Hemphillian -9.50† 10 Dam 2002

Fox and Koch RR at FM 211 33.30 -101.50 6.80 Late Hemphillian -6.50* 25 2003 Yellowhouse Fox and Koch 33.50 -101.60 6.80 Late Hemphillian -5.23* 34 Canyon A2 2003 Yellowhouse Fox and Koch 33.50 -101.60 6.80 Late Hemphillian -6.98* 21 Canyon B2 2003 Fox and Koch Coffee Ranch, TX 35.44 -100.31 6.65 Late Hemphillian -6.92* 21 2003 Wang et al. Coffee Ranch, TX 35.44 -100.31 6.65 Late Hemphillian -6.90† 27 1994; Passey et al. 2002 Fox and Koch Bellview 34.90 -103.10 6.40 Late Hemphillian -7.20* 20 2003 Fox and Koch Alien Canyon A 37.00 -100.60 4.20 Late Blancan -4.70* 38 2003 Fox and Koch Alien Canyon B 37.00 -100.60 3.99 Late Blancan -4.80* 38 2003 Fox and Fisher Jack Swayze Quarry 37.22 -99.47 8.00 Late Hemphillian -9.76† 8 2004 Fox and Fisher V.V. Parker Pits 36.19 -100.33 8.00 Late Hemphillian -9.60† 9 2004 Fox and Fisher Port of Entry Pit 36.11 -99.78 8.00 Late Hemphillian -10.46† 4 2004 Damuth et al. Big Springs 43.00 -98.00 2.30 Late Blancan -3.64† 59 2002; Passey et al. 2002 Passey et al. Big Springs 42.00 -98.00 2.30 Late Blancan -2.10† 69 2002 Passey et al. Quinn Gravel Pit 43.00 -101.00 2.50 Late Blancan -3.87† 58 2002 Passey et al. South Wind Prospect 42.00 -98.00 2.50 Late Blancan -8.25† 27 2002 148

APPENDIX D1: STABLE ISOTOPES

Passey et al. Hall Gravel Pit 42.43 -99.93 3.00 Late Blancan -3.10† 63 2002 Damuth et al. Broadwater 41.60 -102.74 3.00 Late Blancan -4.93† 50 2002; Passey et al. 2002 Passey et al. Lisco 41.51 -102.58 4.00 Late Blancan -6.30† 41 2002 Passey 2002, Devil's Nest Airstrip 42.49 -97.43 5.00 Late Hemphillian -4.20† 55 Damuth 2002 Passey et al. Ashton Quarry 41.21 -98.45 6.00 Late Hemphillian -8.40† 21 2002 Passey et al. Ashton Local Fauna 42.00 -99.00 6.00 Late Hemphillian -9.30† 15 2002 Damuth et al. Mailbox Prospect 42.23 -98.07 6.00 Late Hemphillian -9.20† 15 2002; Passey et al. 2002 Passey et al. Rick Irwin 42.43 -99.34 6.00 Late Hemphillian -6.46† 34 2002 Uptegrove local Passey et al. 41.15 -102.54 6.00 Late Hemphillian -9.75† 12 fauna 2002 Passey et al. ZX-Bar 42.19 -103.77 6.00 Late Hemphillian -8.93† 17 2002 Damuth et al. Cambridge local 40.52 -100.38 7.00 Late Hemphillian -9.20† 12 2002; Passey fauna et al. 2002 Passey et al. Greenwood Canyon 41.27 -103.03 7.00 Late Hemphillian -8.02† 20 2002 Passey et al. Oshkosh local fauna 41.20 -102.23 7.00 Late Hemphillian -9.27† 12 2002 Damuth et al. Aphelops Draw Q#1 42.20 -103.79 8.00 Late Hemphillian -9.50† 10 2002; Passey et al. 2002 Passey et al. Lemoyne Quarry 41.46 -101.88 8.00 Late Hemphillian -8.50† 17 2002 Passey et al. The Pits 42.11 -103.46 8.00 Late Hemphillian -9.70† 9 2002 Passey et al. Mt. Blanco 34.00 -101.00 2.00 Late Blancan -6.00† 43 2002 Passey et al. Mt. Blanco 34.00 -101.00 2.00 Late Blancan -1.00† 77 2002 Red Light/Love Passey et al. 31.00 -105.00 2.00 Late Blancan -0.20† 82 Ranch 2002 Passey et al. Bridwell Ranch 34.00 -101.00 3.00 Late Blancan 0.10† 84 2002 Passey et al. Bridwell Ranch 34.00 -101.00 3.00 Late Blancan -3.90† 57 2002 Passey et al. Bailey Farm 35.00 -101.00 6.00 Late Hemphillian -5.90† 37 2002 Passey et al. Cleo Hibbard Ranch 35.00 -101.00 6.00 Late Hemphillian -6.10† 36 2002 149

APPENDIX D1: STABLE ISOTOPES

Janes-Prentice Passey et al. 33.00 -102.00 7.00 Late Hemphillian -9.30† 11 Gravel Pit 2002 Passey et al. Box T Quarry 36.14 -100.05 8.00 Late Hemphillian -9.50† 10 2002 Safford-Duncan 32.00 -109.00 3.00 Late Blancan -9.20† 20 Clouthier 1994 Magill Ranch 42.00 -100.00 4.00 Late Blancan -10.95† 7 Clouthier 1994 Box T Quarry 36.14 -100.05 6.50 Late Hemphillian -8.80† 15 Clouthier 1994

150

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Location Name Latitude Longitude Age Time NALMA MAP Reference Slice (mm) South Bijou Hill 43.49 -99.27 14.65 Early Barstovian 332.82 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.66 Early Barstovian 399.09 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.68 Early Barstovian 286.61 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.69 Early Barstovian 292.52 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.70 Early Barstovian 372.08 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.99 Early Barstovian 345.22 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 15.00 Early Barstovian 251.36 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 15.08 Early Barstovian 427.34 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 15.09 Early Barstovian 367.96 Retallack, pers comm.

Mitchell 42.20 -103.79 16.10 Early Hemingfordian 349.78 Retallack, pers comm.

Mitchell 42.20 -103.79 16.11 Early Hemingfordian 325.81 Retallack, pers comm.

Mitchell 42.20 -103.79 16.15 Early Hemingfordian 402.16 Retallack, pers comm.

Mitchell 42.20 -103.79 16.16 Early Hemingfordian 385.03 Retallack, pers comm.

Martin 43.14 -101.88 16.70 Early Hemingfordian 697.46 Retallack, pers comm.

Mitchell 42.19 -103.77 16.71 Early Hemingfordian 659.37 Retallack, pers comm.

Chadron 42.55 -102.86 17.67 Early Hemingfordian 519.13 Retallack, pers comm.

Chadron 42.55 -102.86 17.67 Early Hemingfordian 456.88 Retallack, pers comm.

Chadron 42.58 -103.04 17.81 Early Hemingfordian 543.97 Retallack, pers comm.

Chadron 42.58 -103.04 17.92 Early Hemingfordian 343.78 Retallack, pers comm.

Marsland 42.37 -103.30 17.93 Early Hemingfordian 462.52 Retallack, pers comm.

Marsland 42.37 -103.30 17.97 Early Hemingfordian 544.17 Retallack, pers comm.

Marsland 42.37 -103.30 18.02 Early Hemingfordian 424.49 Retallack, pers comm.

Marsland 42.37 -103.30 18.06 Early Hemingfordian 529.56 Retallack, pers comm. 151

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Marsland 42.37 -103.30 18.10 Early Hemingfordian 413.40 Retallack, pers comm.

Chadron 42.58 -103.06 18.31 Early Hemingfordian 350.02 Retallack, pers comm.

Chadron 42.58 -103.06 18.35 Early Hemingfordian 326.03 Retallack, pers comm.

Hemingford 42.42 -103.06 18.39 Early Hemingfordian 338.12 Retallack, pers comm.

Chadron 42.58 -103.06 18.39 Early Hemingfordian 319.97 Retallack, pers comm.

Hemingford 42.42 -103.06 18.42 Early Hemingfordian 396.71 Retallack, pers comm.

Chadron 42.58 -103.06 18.43 Early Hemingfordian 350.10 Retallack, pers comm.

Chadron 42.55 -102.86 18.44 Early Hemingfordian 307.75 Retallack, pers comm.

Hemingford 42.42 -103.06 18.46 Early Hemingfordian 326.09 Retallack, pers comm.

Chadron 42.55 -102.86 18.51 Early Hemingfordian 554.52 Retallack, pers comm.

Agate 42.42 -103.73 18.61 Early Hemingfordian 375.40 Retallack, pers comm.

Agate 42.42 -103.73 18.63 Early Hemingfordian 381.27 Retallack, pers comm.

Agate 42.42 -103.73 18.65 Early Hemingfordian 387.11 Retallack, pers comm.

Agate 42.42 -103.73 18.66 Early Hemingfordian 410.11 Retallack, pers comm.

Agate 42.42 -103.73 18.70 Early Hemingfordian 398.73 Retallack, pers comm.

Hemingford 42.37 -103.02 18.71 Early Hemingfordian 396.97 Retallack, pers comm.

Agate 42.42 -103.73 18.72 Early Hemingfordian 351.81 Retallack, pers comm.

Agate 42.42 -103.73 18.73 Early Hemingfordian 410.21 Retallack, pers comm.

Hemingford 42.37 -103.02 18.77 Early Hemingfordian 458.04 Retallack, pers comm.

Agate 42.42 -103.73 18.77 Early Hemingfordian 351.87 Retallack, pers comm.

Agate 42.42 -103.73 18.79 Early Hemingfordian 321.55 Retallack, pers comm.

Agate 42.42 -103.73 18.81 Early Hemingfordian 375.64 Retallack, pers comm.

Agate 42.42 -103.73 18.84 Early Hemingfordian 438.42 Retallack, pers comm.

Agate 42.42 -103.73 18.87 Early Hemingfordian 339.94 Retallack, pers comm.

Eagle Crags 42.72 -103.88 18.87 Early Hemingfordian 345.98 Retallack, pers comm. 152

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Agate 42.42 -103.73 18.88 Early Hemingfordian 345.99 Retallack, pers comm.

Agate 42.42 -103.73 18.90 Early Hemingfordian 421.76 Retallack, pers comm.

Eagle Crags 42.72 -103.88 18.90 Early Hemingfordian 352.02 Retallack, pers comm.

Eagle Crags 42.72 -103.88 18.95 Early Hemingfordian 460.48 Retallack, pers comm.

Agate 42.42 -103.73 19.00 Early Hemingfordian 364.06 Retallack, pers comm.

Mission 43.32 -100.85 19.00 Early Hemingfordian 483.84 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.01 Early Hemingfordian 334.00 Retallack, pers comm.

Mission 43.32 -100.85 19.02 Early Hemingfordian 328.81 Retallack, pers comm.

Agate 42.42 -103.73 19.03 Early Hemingfordian 404.91 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.03 Early Hemingfordian 352.16 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.06 Early Hemingfordian 421.98 Retallack, pers comm.

Agate 42.42 -103.73 19.06 Early Hemingfordian 327.95 Retallack, pers comm.

Mission 43.32 -100.85 19.07 Early Hemingfordian 316.91 Retallack, pers comm.

Agate 42.42 -103.73 19.08 Early Hemingfordian 375.97 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.09 Early Hemingfordian 315.67 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.11 Early Hemingfordian 346.23 Retallack, pers comm.

Mission 43.32 -100.85 19.11 Early Hemingfordian 457.97 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.13 Early Hemingfordian 405.04 Retallack, pers comm.

Mission 43.32 -100.85 19.15 Early Hemingfordian 340.77 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.16 Early Hemingfordian 340.24 Retallack, pers comm.

Mission 43.32 -100.85 19.17 Early Hemingfordian 334.88 Retallack, pers comm.

Mission 43.32 -100.85 19.18 Early Hemingfordian 452.79 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.20 Early Hemingfordian 352.35 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.22 Early Hemingfordian 416.56 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.26 Early Hemingfordian 358.41 Retallack, pers comm. 153

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Eagle Crags 42.72 -103.88 19.28 Early Hemingfordian 346.42 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.30 Early Hemingfordian 427.95 Retallack, pers comm.

Agate 42.42 -103.73 19.33 Early Hemingfordian 376.37 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.35 Early Hemingfordian 328.24 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.37 Early Hemingfordian 322.11 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.39 Early Hemingfordian 416.80 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.45 Early Hemingfordian 352.63 Retallack, pers comm.

Agate 42.42 -103.73 19.46 Early Hemingfordian 358.60 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.47 Early Hemingfordian 358.64 Retallack, pers comm.

Agate 42.42 -103.73 19.48 Early Hemingfordian 439.30 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.49 Early Hemingfordian 428.23 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.54 Early Hemingfordian 417.00 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.57 Early Hemingfordian 411.36 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.59 Early Hemingfordian 340.69 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.61 Early Hemingfordian 316.16 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.65 Early Hemingfordian 346.82 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.68 Early Hemingfordian 417.20 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.71 Early Hemingfordian 370.83 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.73 Early Hemingfordian 434.17 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.79 Early Hemingfordian 388.56 Retallack, pers comm.

Eagle Crags 42.72 103.88 19.82 Early Hemingfordian 405.97 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.84 Early Hemingfordian 439.90 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.87 Early Hemingfordian 428.77 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.90 Early Hemingfordian 406.09 Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.94 Early Hemingfordian 423.23 Retallack, pers comm. 154

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Eagle Crags 42.72 -103.88 19.98 Early Hemingfordian 417.62 Retallack, pers comm.

Eagle Crags 42.72 -103.88 20.01 Early Hemingfordian 406.23 Retallack, pers comm.

Eagle Crags 42.72 -103.88 20.04 Early Hemingfordian 423.38 Retallack, pers comm.

Eagle Crags 42.72 -103.88 20.12 Early Hemingfordian 383.13 Retallack, pers comm.

Eagle Crags 42.72 -103.88 20.22 Early Hemingfordian 467.90 Retallack, pers comm.

Norden bridge 42.79 -100.03 21.79 Early Arikareean 409.49 Retallack, pers comm.

Norden bridge 42.79 -100.03 21.82 Early Arikareean 420.33 Retallack, pers comm.

Norden bridge 42.79 -100.03 21.88 Early Arikareean 441.64 Retallack, pers comm.

Mission 43.32 -100.87 21.96 Early Arikareean 462.10 Retallack, pers comm.

Mission 43.32 -100.87 21.98 Early Arikareean 337.55 Retallack, pers comm.

Mission 43.32 -100.87 22.00 Early Arikareean 355.41 Retallack, pers comm.

Mission 43.32 -100.87 22.03 Early Arikareean 451.47 Retallack, pers comm.

Agate 42.42 -103.73 22.03 Early Arikareean 434.51 Retallack, pers comm.

Mission 43.32 -100.87 22.06 Early Arikareean 367.21 Retallack, pers comm.

Mission 43.32 -100.87 22.07 Early Arikareean 373.06 Retallack, pers comm.

Norden bridge 42.42 -103.73 22.10 Early Arikareean 441.77 Retallack, pers comm.

Mission 43.32 -100.87 22.10 Early Arikareean 456.95 Retallack, pers comm.

Agate 42.42 -103.73 22.18 Early Arikareean 382.97 Retallack, pers comm.

Mission 43.32 -100.87 22.19 Early Arikareean 378.99 Retallack, pers comm.

Mission 43.32 -100.87 22.22 Early Arikareean 367.38 Retallack, pers comm.

Mission 43.32 -100.87 22.25 Early Arikareean 478.40 Retallack, pers comm.

Agate 42.42 -103.73 22.27 Early Arikareean 388.85 Retallack, pers comm.

Mission 43.32 -100.87 22.28 Early Arikareean 373.28 Retallack, pers comm.

Mission 43.32 -100.87 22.30 Early Arikareean 343.83 Retallack, pers comm.

Mission 43.32 -100.87 22.32 Early Arikareean 396.37 Retallack, pers comm. 155

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Agate 42.42 -103.73 22.44 Early Arikareean 462.21 Retallack, pers comm.

Agate 42.42 -103.73 22.55 Early Arikareean 383.07 Retallack, pers comm.

Agate 42.42 -103.73 22.70 Early Arikareean 434.71 Retallack, pers comm.

Agate 42.42 -103.73 22.87 Early Arikareean 377.26 Retallack, pers comm.

Smiley Canyon 42.66 -103.55 23.00 Early Arikareean 407.53 Retallack, pers comm.

Echo Quarry 42.10 -103.44 15.00 Early Barstovian 2731.62 Wang et al. 1994; Damuth et al. 2002; Passey et al. 2002 West Surface Quarry 42.09 -103.43 15.00 Early Barstovian Wang et al. 1994; Passey et al. 2002 Thompson Quarry 42.19 -103.75 17.50 Early Hemingfordian 2138.93 Damuth et al. 2002; Passey et al. 2002 Eubanks Fauna 40.52 -103.55 15.00 Early Barstovian 1107.90 Damuth et al. 2002 (CP75B): Observation Quarry 42.42 -102.50 15.00 Early Barstovian 1059.21 Damuth et al. 2002 (CP111): Foley Quarry 42.24 -103.02 17.00 Early Hemingfordian 1287.02 Damuth et al. 2002 (CP107): Ginn Quarry 42.39 -102.47 17.00 Early Hemingfordian 600.42 Damuth et al. 2002 (CP109A): Aletomeryx Quarry 42.45 -102.01 18.00 Early Hemingfordian 2536.87 Damuth et al. 2002 (CP105): University of Kansas 40.54 -103.16 18.00 Early Hemingfordian 841.60 Damuth et al. 2002 Quarry A (CP71):

Flint Hill Local 43.08 -101.52 18.00 Early Hemingfordian 938.73 Damuth et al. 2002 Fauna (CP88): Humbug Quarry 42.10 -103.44 15.00 Early Barstovian 2560.14 Damuth et al. 2002 (CP110): Marsland 42.69 -103.41 18.50 Early Hemingfordian 900.00 Axelrod 1985 Norden Bridge 42.80 -100.00 14.30 Middle Barstovian 190.08 Damuth et al. 2002; Fox Quarry and Koch 2003 Myers Farm 40.10 -98.47 12.00 Middle Barstovian 1888.09 Damuth et al. 2002; Fox and Fisher 2004 Merritt Dam 42.65 -100.86 9.19 Middle Clarendonian 370.97 Retallack, pers comm.

Merritt Dam 42.65 -100.86 9.36 Middle Clarendonian 301.65 Retallack, pers comm.

Merritt Dam 42.65 -100.86 9.40 Middle Clarendonian 348.40 Retallack, pers comm.

Merritt Dam 42.65 -100.86 9.98 Middle Clarendonian 348.72 Retallack, pers comm.

Mitchell 42.17 -103.73 10.00 Middle Clarendonian 422.26 Retallack, pers comm.

Merritt Dam 42.65 -100.86 10.02 Middle Clarendonian 277.87 Retallack, pers comm. 156

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Olcott Hill 42.17 -103.73 10.11 Middle Clarendonian 352.80 Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.26 Middle Clarendonian 411.94 Retallack, pers comm.

Valentine 42.91 -100.48 10.32 Middle Clarendonian 404.96 Retallack, pers comm.

Valentine 42.91 -100.48 10.35 Middle Clarendonian 360.43 Retallack, pers comm.

Valentine 42.91 -100.48 10.36 Middle Clarendonian 542.45 Retallack, pers comm.

Morland 39.37 -100.08 10.42 Middle Clarendonian 386.64 Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.45 Middle Clarendonian 363.88 Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.58 Middle Clarendonian 385.57 Retallack, pers comm.

Big Spring Canyon 43.11 -101.94 10.60 Middle Clarendonian 266.17 Damuth et al. 2002; Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.73 Middle Clarendonian 330.70 Retallack, pers comm.

Morland 39.37 -100.08 11.10 Middle Clarendonian 418.58 Retallack, pers comm.

Valentine 42.91 -100.48 11.41 Middle Clarendonian 339.97 Retallack, pers comm.

Valentine 42.91 -100.48 11.43 Middle Clarendonian 322.27 Retallack, pers comm.

Valentine 42.91 -100.48 11.45 Middle Clarendonian 363.31 Retallack, pers comm.

Valentine 42.91 -100.48 11.46 Middle Clarendonian 340.10 Retallack, pers comm.

Valentine 42.91 -100.48 11.49 Middle Clarendonian 334.28 Retallack, pers comm.

Olcott Hill 42.17 -103.73 11.62 Middle Barstovian 473.37 Retallack, pers comm.

Norden quarry 42.79 -100.03 11.67 Middle Barstovian 403.53 Retallack, pers comm.

Norden quarry 42.79 -100.03 11.68 Middle Barstovian 376.03 Retallack, pers comm.

Norden quarry 42.79 -100.03 11.69 Middle Barstovian 516.62 Retallack, pers comm.

Olcott Hill 42.17 -103.73 11.71 Middle Barstovian 347.71 Retallack, pers comm.

Broadwater 41.55 -102.72 12.96 Middle Barstovian 550.84 Retallack, pers comm.

Broadwater 41.55 -102.72 13.07 Middle Barstovian 387.94 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.05 Middle Barstovian 369.74 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.06 Middle Barstovian 380.61 Retallack, pers comm. 157

APPENDIX D2: MEAN ANNUAL PRECIPITATION

South Bijou Hill 43.49 -99.27 14.07 Middle Barstovian 353.33 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.08 Middle Barstovian 438.45 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.09 Middle Barstovian 353.40 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.10 Middle Barstovian 347.89 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.10 Middle Barstovian 412.69 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.12 Middle Barstovian 308.43 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.12 Middle Barstovian 342.42 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.13 Middle Barstovian 423.25 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.14 Middle Barstovian 342.45 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.14 Middle Barstovian 308.50 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.15 Middle Barstovian 325.63 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.16 Middle Barstovian 407.66 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.16 Middle Barstovian 331.32 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.17 Middle Barstovian 302.82 Retallack, pers comm.

South Bijou Hill 43.49 -99.27 14.18 Middle Barstovian 308.61 Retallack, pers comm.

Snake Creek Fauna 42.11 -103.46 9.00 Middle Clarendonian 604.90 Damuth et al. 2002 (CP115B): Blue Jay Quarry 42.42 -98.15 9.00 Middle Clarendonian 1590.65 Damuth et al. 2002 (CP116B): Wakeeney Creek 39.05 -99.45 10.00 Middle Clarendonian 266.54 Damuth et al. 2002 Fauna (CP123A): Little Beaver B 42.90 -100.47 10.00 Middle Clarendonian 1402.74 Damuth et al. 2002 Quarry (CP116A): Trail Creek Quarry 41.25 -104.43 12.00 Middle Barstovian 325.86 Damuth et al. 2002 Local Fauna (CP56):

Kennesaw Fauna, 40.59 -103.29 12.00 Middle Barstovian 1143.92 Damuth et al. 2002 (CP76): Carrot Top Quarry 42.47 -100.04 13.50 Middle Barstovian 1735.33 Damuth et al. 2002 (CP114A) Horse and Mastodon 40.49 -104.04 13.50 Middle Barstovian 633.87 Damuth et al. 2002 Quarry (CP75C):

Kilgore 42.80 -101.01 13- Middle Barstovian 825.00 MacGinitie 1962; Axelrod 14 1985 Beaver Co. 36.75 -100.48 11.00 Middle Clarendonian 825.00 Axelrod 1985 158

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Clarendon 34.93 -100.88 11.00 Middle Clarendonian 760.00 Axelrod 1985 Garden Co. 41.40 -102.35 NA Middle Clarendonian 500.00 Thomasson 1980 Borchers Badlands 37.18 -100.37 2.00 Late Blancan 438.84 Retallack, pers comm. north Borchers Badlands 37.16 -100.37 2.12 Late Blancan 562.96 Retallack, pers comm. south Borchers Badlands 37.16 -100.37 2.23 Late Blancan 597.68 Retallack, pers comm. south Borchers Badlands 37.16 -100.37 2.23 Late Blancan 474.19 Retallack, pers comm. south Ainsworth 42.82 -100.56 2.25 Late Blancan 393.11 Retallack, pers comm.

Ainsworth 42.63 -99.84 2.26 Late Blancan 365.95 Retallack, pers comm.

Long Pine 42.65 -99.84 2.26 Late Blancan 332.42 Retallack, pers comm.

Ainsworth 42.65 -99.84 2.27 Late Blancan 440.49 Retallack, pers comm.

Borchers Badlands 37.16 -100.37 2.37 Late Blancan 558.69 Retallack, pers comm. south Ainsworth 42.68 -99.98 2.44 Late Blancan 315.70 Retallack, pers comm.

Borchers Badlands 37.16 -100.37 2.45 Late Blancan 449.31 Retallack, pers comm. south Ainsworth 42.68 -99.98 2.47 Late Blancan 441.22 Retallack, pers comm.

Borchers Badlands 37.16 -100.37 2.50 Late Blancan 549.79 Retallack, pers comm. south Borchers Badlands 37.16 -100.37 2.54 Late Blancan 386.67 Retallack, pers comm. south Broadwater 41.60 -102.76 2.61 Late Blancan 309.71 Retallack, pers comm.

Borchers Badlands 37.16 -100.37 2.62 Late Blancan 397.42 Retallack, pers comm. south Borchers Badlands 37.16 -100.37 2.64 Late Blancan 554.40 Retallack, pers comm. south Borchers Badlands 37.18 -100.37 2.65 Late Blancan 554.57 Retallack, pers comm. north Borchers Badlands 37.16 -100.37 2.73 Late Blancan 508.24 Retallack, pers comm. south Borchers Badlands 37.16 -100.37 2.81 Late Blancan 503.53 Retallack, pers comm. south Borchers Badlands 37.18 -100.37 2.84 Late Blancan 554.72 Retallack, pers comm. north Borchers Badlands 37.18 -100.37 3.04 Late Blancan 503.86 Retallack, pers comm. north Borchers Badlands 37.18 -100.37 3.27 Late Blancan 607.09 Retallack, pers comm. north Borchers Badlands 37.18 -100.37 3.38 Late Blancan 429.36 Retallack, pers comm. north 159

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Borchers Badlands 37.18 -100.37 3.45 Late Blancan 550.68 Retallack, pers comm. north Borchers Badlands 37.18 -100.37 3.56 Late Blancan 537.08 Retallack, pers comm. north Crooked Creek north 37.18 -100.39 3.67 Late Blancan 397.97 Retallack, pers comm.

Broadwater 41.60 -102.76 3.76 Late Blancan 333.11 Retallack, pers comm.

Crooked Creek north 37.18 -100.39 3.82 Late Blancan 460.24 Retallack, pers comm.

Meade 37.22 -100.48 3.82 Late Blancan 521.22 Retallack, pers comm.

Meade 37.22 -100.48 3.91 Late Blancan 448.29 Retallack, pers comm.

Crooked Creek north 37.18 -100.39 3.93 Late Blancan 354.52 Retallack, pers comm.

Meade 37.22 -100.48 4.00 Late Blancan 463.27 Retallack, pers comm.

Crooked Creek north 37.18 -100.39 4.05 Late Blancan 387.43 Retallack, pers comm.

Broadwater 41.60 -102.76 4.09 Late Blancan 472.14 Retallack, pers comm.

Crooked Creek north 37.18 -100.39 4.10 Late Blancan 518.85 Retallack, pers comm.

Meade 37.22 -100.48 4.10 Late Blancan 330.75 Retallack, pers comm.

Meade 37.22 -100.48 4.17 Late Blancan 374.87 Retallack, pers comm.

Meade 37.22 -100.48 4.23 Late Blancan 570.62 Retallack, pers comm.

Crooked Creek north 37.18 -100.39 4.27 Late Blancan 365.74 Retallack, pers comm.

Broadwater 41.60 -102.76 4.43 Late Blancan 361.51 Retallack, pers comm.

Broadwater 41.60 -102.76 4.43 Late Blancan 275.12 Retallack, pers comm.

Broadwater 41.60 -102.76 4.59 Late Blancan 339.13 Retallack, pers comm.

Broadwater 41.60 -102.76 4.69 Late Blancan 426.46 Retallack, pers comm.

Scott Lake 38.63 -100.81 4.97 Late Blancan 380.51 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.07 Late Blancan 325.31 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.12 Late Blancan 385.95 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.23 Late Blancan 417.73 Retallack, pers comm.

Broadwater 41.60 -102.74 5.25 Late Blancan 421.53 Retallack, pers comm. 160

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Broadwater 41.60 -102.76 5.27 Late Blancan 516.88 Retallack, pers comm.

Broadwater 41.60 -102.74 5.32 Late Blancan 442.45 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.35 Late Hemphillian 396.72 Retallack, pers comm.

Lisco 41.52 -102.65 5.42 Late Hemphillian 316.72 Retallack, pers comm.

Harrisburg 41.50 -103.72 5.45 Late Hemphillian 421.85 Retallack, pers comm.

Kimball 41.20 -103.65 5.45 Late Hemphillian 287.43 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.46 Late Hemphillian 386.07 Retallack, pers comm.

Broadwater 41.60 -102.76 5.56 Late Hemphillian 275.46 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.58 Late Hemphillian 358.94 Retallack, pers comm.

Broadwater 41.60 -102.76 5.59 Late Hemphillian 400.41 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.66 Late Hemphillian 273.49 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.71 Late Hemphillian 285.24 Retallack, pers comm.

Almena 39.88 -99.69 5.71 Late Hemphillian 398.89 Retallack, pers comm.

Almena 39.88 -99.71 5.72 Late Hemphillian 321.30 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.73 Late Hemphillian 280.56 Retallack, pers comm.

Broadwater 41.60 -102.74 5.75 Late Hemphillian 281.48 Retallack, pers comm.

Almena 39.88 -99.71 5.75 Late Hemphillian 315.59 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.75 Late Hemphillian 292.35 Retallack, pers comm.

Clayton 39.76 -100.09 5.76 Late Hemphillian 360.79 Retallack, pers comm.

Almena 39.88 -99.69 5.77 Late Hemphillian 355.25 Retallack, pers comm.

Harrisburg 41.50 -103.72 5.78 Late Hemphillian 316.82 Retallack, pers comm.

Kimball 41.21 -103.65 5.78 Late Hemphillian 339.77 Retallack, pers comm.

Clayton 39.76 -100.09 5.78 Late Hemphillian 274.67 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.79 Late Hemphillian 344.07 Retallack, pers comm.

Almena 39.88 -99.71 5.80 Late Hemphillian 355.28 Retallack, pers comm. 161

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Clayton 39.76 -100.09 5.81 Late Hemphillian 292.39 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.81 Late Hemphillian 430.67 Retallack, pers comm.

Clayton 39.76 -100.09 5.84 Late Hemphillian 360.87 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.84 Late Hemphillian 388.26 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.84 Late Hemphillian 347.96 Retallack, pers comm.

Almena 39.88 -99.71 5.84 Late Hemphillian 409.70 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.87 Late Hemphillian 349.76 Retallack, pers comm.

Clayton 39.76 -100.09 5.88 Late Hemphillian 404.42 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.90 Late Hemphillian 274.74 Retallack, pers comm.

Clayton 39.76 -100.09 5.93 Late Hemphillian 409.80 Retallack, pers comm.

Scott Lake 38.63 -100.81 5.94 Late Hemphillian 319.88 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.94 Late Hemphillian 315.74 Retallack, pers comm.

Clayton 39.76 -100.09 5.97 Late Hemphillian 446.35 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 5.99 Late Hemphillian 321.52 Retallack, pers comm.

Hays 39.15 -99.28 6.00 Late Hemphillian 249.58 Retallack, pers comm.

Crooked Creek south 37.16 -100.39 6.04 Late Hemphillian 327.29 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.04 Late Hemphillian 535.78 Retallack, pers comm.

Clayton 39.76 -100.09 6.09 Late Hemphillian 393.94 Retallack, pers comm.

Clayton 39.76 -100.09 6.10 Late Hemphillian 539.07 Retallack, pers comm.

Lisco 41.52 -102.65 6.17 Late Hemphillian 311.22 Retallack, pers comm.

Ogalalla 41.20 -101.66 6.21 Late Hemphillian 351.19 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.27 Late Hemphillian 302.79 Retallack, pers comm.

Clayton 39.76 -100.09 6.30 Late Hemphillian 539.38 Retallack, pers comm.

Ellis 39.06 -99.57 6.34 Late Hemphillian 353.26 Retallack, pers comm.

Ellis 39.04 -99.53 6.34 Late Hemphillian 438.32 Retallack, pers comm. 162

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Scott Lake 38.63 -100.81 6.40 Late Hemphillian 331.34 Retallack, pers comm.

Broadwater 41.60 -102.74 6.41 Late Hemphillian 293.55 Retallack, pers comm.

Clayton 39.76 -100.09 6.46 Late Hemphillian 492.06 Retallack, pers comm.

Clayton 39.76 -100.09 6.50 Late Hemphillian 553.44 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.50 Late Hemphillian 273.67 Retallack, pers comm.

Ellis 39.05 -99.57 6.51 Late Hemphillian 325.34 Retallack, pers comm.

Clayton 39.76 -100.09 6.54 Late Hemphillian 521.05 Retallack, pers comm.

Harrisburg 41.50 -103.72 6.56 Late Hemphillian 275.81 Retallack, pers comm.

Broadwater 41.60 -102.74 6.57 Late Hemphillian 334.28 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.58 Late Hemphillian 314.36 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.65 Late Hemphillian 337.05 Retallack, pers comm.

Ellis 39.06 -99.57 6.68 Late Hemphillian 347.78 Retallack, pers comm.

Ellis 39.04 -99.53 6.68 Late Hemphillian 417.75 Retallack, pers comm.

Hays, KS 39.15 -99.28 6.68 Late Hemphillian 358.83 Retallack, pers comm.

Clayton 39.76 -100.09 6.74 Late Hemphillian 316.36 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.76 Late Hemphillian 320.12 Retallack, pers comm.

Ogalalla 41.20 -101.66 6.76 Late Hemphillian 269.87 Retallack, pers comm.

Clayton 39.76 -100.09 6.77 Late Hemphillian 327.89 Retallack, pers comm.

Clayton 39.76 -100.09 6.83 Late Hemphillian 540.20 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.83 Late Hemphillian 402.61 Retallack, pers comm.

Scott Lake 38.63 -100.81 6.91 Late Hemphillian 397.33 Retallack, pers comm.

Ellis 39.01 -99.57 7.02 Late Hemphillian 308.32 Retallack, pers comm.

Ellis 39.13 -99.55 7.02 Late Hemphillian 285.17 Retallack, pers comm.

Hays 39.01 -99.34 7.02 Late Hemphillian 279.31 Retallack, pers comm.

Lisco 41.52 -102.65 7.03 Late Hemphillian 288.00 Retallack, pers comm. 163

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Scott Lake 38.63 -100.81 7.06 Late Hemphillian 342.78 Retallack, pers comm.

Hays 38.88 -99.46 7.07 Late Hemphillian 237.57 Retallack, pers comm.

Hays 38.88 -99.46 7.12 Late Hemphillian 267.48 Retallack, pers comm.

Ogalalla 41.20 -101.66 7.13 Late Hemphillian 276.00 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.14 Late Hemphillian 308.78 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.22 Late Hemphillian 413.32 Retallack, pers comm.

Harrisburg 41.50 -103.72 7.22 Late Hemphillian 373.98 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.32 Late Hemphillian 397.48 Retallack, pers comm.

Ellis 39.04 -99.53 7.36 Late Hemphillian 364.42 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.42 Late Hemphillian 392.18 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.50 Late Hemphillian 386.84 Retallack, pers comm.

Ash Hollow 41.29 -102.12 7.52 Late Hemphillian 270.27 Retallack, pers comm.

Ellis 39.01 -99.57 7.53 Late Hemphillian 255.69 Retallack, pers comm.

Ogalalla 41.20 -101.66 7.59 Late Hemphillian 282.16 Retallack, pers comm.

Ellis 39.04 -99.55 7.60 Late Hemphillian 567.07 Retallack, pers comm.

Scott Lake 38.63 -100.81 7.65 Late Hemphillian 291.53 Retallack, pers comm.

Ellis 39.04 -99.53 7.70 Late Hemphillian 507.60 Retallack, pers comm.

Ellis 39.04 -99.53 7.70 Late Hemphillian 353.47 Retallack, pers comm.

Ellis 39.04 -99.53 7.70 Late Hemphillian 453.81 Retallack, pers comm.

Ellis 39.13 -99.55 7.70 Late Hemphillian 386.17 Retallack, pers comm.

Ellis 39.01 -99.57 7.70 Late Hemphillian 261.66 Retallack, pers comm.

Ash Hollow 41.29 -102.12 7.92 Late Hemphillian 418.68 Retallack, pers comm.

Ellis 39.04 -99.55 8.04 Late Hemphillian 359.04 Retallack, pers comm.

Ash Hollow 41.29 -102.12 8.06 Late Hemphillian 341.44 Retallack, pers comm.

Lisco 41.52 -102.65 8.11 Late Hemphillian 363.54 Retallack, pers comm. 164

APPENDIX D2: MEAN ANNUAL PRECIPITATION

Ellis 39.04 -99.53 8.38 Late Hemphillian 353.57 Retallack, pers comm.

Ellis 39.01 -99.57 8.38 Late Hemphillian 493.40 Retallack, pers comm.

Big Springs 43.00 -98.00 2.30 Late Blancan 323.53 Damuth et al. 2002; Passey et al. 2002 Broadwater 41.60 -102.74 3.00 Late Blancan 288.47 Damuth et al. 2002; Passey et al. 2002 Devil's Nest Airstrip 42.49 -97.43 5.00 Late Hemphillian 676.24 Passey 2002, Damuth 2002 Mailbox Prospect 42.23 -98.07 6.00 Late Hemphillian 507.36 Damuth et al. 2002; Passey et al. 2002 Cambridge local 40.52 -100.38 7.00 Late Hemphillian 820.20 Damuth et al. 2002; fauna Passey et al. 2002 Aphelops Draw Q#1 42.20 -103.79 8.00 Late Hemphillian 533.87 Damuth et al. 2002; Passey et al. 2002 White Rock Local 39.00 -97.00 2.00 Late Blancan 181.26 Damuth et al. 2002 Fauna (CP131): Sand Draw Local 42.00 -100.00 2.00 Late Blancan 275.54 Damuth et al. 2002 Fauna (CP118): Deer Park Local 37.00 -100.00 3.00 Late Blancan 148.43 Damuth et al. 2002 Fauna (CP130A): Rexroad Local Fauna 37.16 -100.46 3.00 Late Blancan 589.85 Damuth et al. 2002 (CP128C): Santee Local Fauna 42.82 -97.83 4.00 Late Blancan 646.52 Damuth et al. 2002 (CP116F): Honey Creek 42.78 -98.60 5.50 Late Hemphillian 466.46 Damuth et al. 2002 (CP116E): Edson Quarry Fauna 39.09 -101.30 5.50 Late Hemphillian 646.52 Damuth et al. 2002 (CP123D): Minium Quarry 39.24 -100.08 6.50 Late Hemphillian 173.49 Damuth et al. 2002 (CP126): Wray Fauna (CP78): 40.04 -102.13 6.50 Late Hemphillian 520.47 Damuth et al. 2002

Feltz Ranch Fauna, 41.17 -101.53 7.50 Late Hemphillian 561.77 Damuth et al. 2002 Lemoyne Quarry (CP116C): 165

APPENDIX D3: MOLLIC HORIZON

Location Name Latitude Longitude Age Time NALMA Mollic Reference Slice South Bijou Hill 43.49 -99.27 14.65 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.66 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.68 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.69 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.70 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.99 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 15.00 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 15.08 Early Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 15.09 Early Barstovian non- Retallack, pers comm. mollic Mitchell 42.20 -103.79 16.10 Early Hemingfordian mollic Retallack, pers comm.

Mitchell 42.20 -103.79 16.11 Early Hemingfordian near- Retallack, pers comm. mollic Mitchell 42.20 -103.79 16.15 Early Hemingfordian non- Retallack, pers comm. mollic Mitchell 42.20 -103.79 16.16 Early Hemingfordian non- Retallack, pers comm. mollic Martin 43.14 -101.88 16.70 Early Hemingfordian near- Retallack, pers comm. mollic Mitchell 42.19 -103.77 16.71 Early Hemingfordian near- Retallack, pers comm. mollic Chadron 42.55 -102.86 17.67 Early Hemingfordian non- Retallack, pers comm. mollic Chadron 42.55 -102.86 17.67 Early Hemingfordian non- Retallack, pers comm. mollic Chadron 42.58 -103.04 17.81 Early Hemingfordian non- Retallack, pers comm. mollic Chadron 42.58 -103.04 17.92 Early Hemingfordian non- Retallack, pers comm. mollic Marsland 42.37 -103.30 17.93 Early Hemingfordian near- Retallack, pers comm. mollic Marsland 42.37 -103.30 17.97 Early Hemingfordian near- Retallack, pers comm. mollic Marsland 42.37 -103.30 18.02 Early Hemingfordian near- Retallack, pers comm. mollic Marsland 42.37 -103.30 18.06 Early Hemingfordian near- Retallack, pers comm. mollic Marsland 42.37 -103.30 18.10 Early Hemingfordian near- Retallack, pers comm. mollic 166

APPENDIX D3: MOLLIC HORIZON

Chadron 42.58 -103.06 18.31 Early Hemingfordian mollic Retallack, pers comm.

Chadron 42.58 -103.06 18.35 Early Hemingfordian near- Retallack, pers comm. mollic Hemingford 42.42 -103.06 18.39 Early Hemingfordian near- Retallack, pers comm. mollic Chadron 42.58 -103.06 18.39 Early Hemingfordian non- Retallack, pers comm. mollic Hemingford 42.42 -103.06 18.42 Early Hemingfordian non- Retallack, pers comm. mollic Chadron 42.58 -103.06 18.43 Early Hemingfordian non- Retallack, pers comm. mollic Chadron 42.55 -102.86 18.44 Early Hemingfordian non- Retallack, pers comm. mollic Hemingford 42.42 -103.06 18.46 Early Hemingfordian near- Retallack, pers comm. mollic Chadron 42.55 -102.86 18.51 Early Hemingfordian non- Retallack, pers comm. mollic Agate 42.42 -103.73 18.61 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.63 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.65 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.66 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.70 Early Hemingfordian mollic Retallack, pers comm.

Hemingford 42.37 -103.02 18.71 Early Hemingfordian non- Retallack, pers comm. mollic Agate 42.42 -103.73 18.72 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 18.73 Early Hemingfordian mollic Retallack, pers comm.

Hemingford 42.37 -103.02 18.77 Early Hemingfordian non- Retallack, pers comm. mollic Agate 42.42 -103.73 18.77 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 18.79 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 18.81 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.84 Early Hemingfordian mollic Retallack, pers comm.

Agate 42.42 -103.73 18.87 Early Hemingfordian mollic Retallack, pers comm.

Eagle Crags 42.72 -103.88 18.87 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 18.88 Early Hemingfordian mollic Retallack, pers comm. 167

APPENDIX D3: MOLLIC HORIZON

Agate 42.42 -103.73 18.90 Early Hemingfordian mollic Retallack, pers comm.

Eagle Crags 42.72 -103.88 18.90 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 18.95 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 19.00 Early Hemingfordian mollic Retallack, pers comm.

Mission 43.32 -100.85 19.00 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.01 Early Hemingfordian near- Retallack, pers comm. mollic Mission 43.32 -100.85 19.02 Early Hemingfordian non- Retallack, pers comm. mollic Agate 42.42 -103.73 19.03 Early Hemingfordian mollic Retallack, pers comm.

Eagle Crags 42.72 -103.88 19.03 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.06 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 19.06 Early Hemingfordian mollic Retallack, pers comm.

Mission 43.32 -100.85 19.07 Early Hemingfordian non- Retallack, pers comm. mollic Agate 42.42 -103.73 19.08 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.09 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.11 Early Hemingfordian near- Retallack, pers comm. mollic Mission 43.32 -100.85 19.11 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.13 Early Hemingfordian near- Retallack, pers comm. mollic Mission 43.32 -100.85 19.15 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.16 Early Hemingfordian near- Retallack, pers comm. mollic Mission 43.32 -100.85 19.17 Early Hemingfordian non- Retallack, pers comm. mollic Mission 43.32 -100.85 19.18 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.20 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.22 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.26 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.28 Early Hemingfordian near- Retallack, pers comm. mollic 168

APPENDIX D3: MOLLIC HORIZON

Eagle Crags 42.72 -103.88 19.30 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 19.33 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.35 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.37 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.39 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.45 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 19.46 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.47 Early Hemingfordian near- Retallack, pers comm. mollic Agate 42.42 -103.73 19.48 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.49 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.54 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.57 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.59 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.61 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.65 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.68 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.71 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.73 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.79 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 103.88 19.82 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.84 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.87 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.90 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.94 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 19.98 Early Hemingfordian near- Retallack, pers comm. mollic 169

APPENDIX D3: MOLLIC HORIZON

Eagle Crags 42.72 -103.88 20.01 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 20.04 Early Hemingfordian near- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 20.12 Early Hemingfordian non- Retallack, pers comm. mollic Eagle Crags 42.72 -103.88 20.22 Early Hemingfordian non- Retallack, pers comm. mollic Norden bridge 42.79 -100.03 21.79 Early Arikareean non- Retallack, pers comm. mollic Norden bridge 42.79 -100.03 21.82 Early Arikareean non- Retallack, pers comm. mollic Norden bridge 42.79 -100.03 21.88 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 21.96 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 21.98 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.00 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.03 Early Arikareean non- Retallack, pers comm. mollic Agate 42.42 -103.73 22.03 Early Arikareean near Retallack, pers comm. mollic Mission 43.32 -100.87 22.06 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.07 Early Arikareean non- Retallack, pers comm. mollic Norden bridge 42.42 -103.73 22.10 Early Arikareean near- Retallack, pers comm. mollic Mission 43.32 -100.87 22.10 Early Arikareean non- Retallack, pers comm. mollic Agate 42.42 -103.73 22.18 Early Arikareean near Retallack, pers comm. mollic Mission 43.32 -100.87 22.19 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.22 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.25 Early Arikareean non- Retallack, pers comm. mollic Agate 42.42 -103.73 22.27 Early Arikareean near Retallack, pers comm. mollic Mission 43.32 -100.87 22.28 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.30 Early Arikareean non- Retallack, pers comm. mollic Mission 43.32 -100.87 22.32 Early Arikareean non- Retallack, pers comm. mollic Agate 42.42 -103.73 22.44 Early Arikareean near Retallack, pers comm. mollic 170

APPENDIX D3: MOLLIC HORIZON

Agate 42.42 -103.73 22.55 Early Arikareean near Retallack, pers comm. mollic Agate 42.42 -103.73 22.70 Early Arikareean near Retallack, pers comm. mollic Agate 42.42 -103.73 22.87 Early Arikareean near Retallack, pers comm. mollic Smiley Canyon 42.66 -103.55 23.00 Early Arikareean non- Retallack, pers comm. mollic Merritt Dam 42.65 -100.86 9.19 Middle Clarendonian non- Retallack, pers comm. mollic Merritt Dam 42.65 -100.86 9.36 Middle Clarendonian non- Retallack, pers comm. mollic Merritt Dam 42.65 -100.86 9.40 Middle Clarendonian non- Retallack, pers comm. mollic Merritt Dam 42.65 -100.86 9.98 Middle Clarendonian non- Retallack, pers comm. mollic Mitchell 42.17 -103.73 10.00 Middle Clarendonian mollic Retallack, pers comm.

Merritt Dam 42.65 -100.86 10.02 Middle Clarendonian non- Retallack, pers comm. mollic Olcott Hill 42.17 -103.73 10.11 Middle Clarendonian mollic Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.26 Middle Clarendonian mollic Retallack, pers comm.

Valentine 42.91 -100.48 10.32 Middle Clarendonian near- Retallack, pers comm. mollic Valentine 42.91 -100.48 10.35 Middle Clarendonian mollic Retallack, pers comm.

Valentine 42.91 -100.48 10.36 Middle Clarendonian non- Retallack, pers comm. mollic Morland 39.37 -100.08 10.42 Middle Clarendonian non Retallack, pers comm. mollic Olcott Hill 42.17 -103.73 10.45 Middle Clarendonian mollic Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.58 Middle Clarendonian mollic Retallack, pers comm.

Big Spring 43.11 -101.94 10.60 Middle Clarendonian non- Damuth et al. 2002; Canyon mollic Retallack, pers comm.

Olcott Hill 42.17 -103.73 10.73 Middle Clarendonian mollic Retallack, pers comm.

Morland 39.37 -100.08 11.10 Middle Clarendonian near- Retallack, pers comm. mollic Valentine 42.91 -100.48 11.41 Middle Clarendonian mollic Retallack, pers comm.

Valentine 42.91 -100.48 11.43 Middle Clarendonian mollic Retallack, pers comm.

Valentine 42.91 -100.48 11.45 Middle Clarendonian mollic Retallack, pers comm. 171

Valentine 42.91 -100.48 11.46 Middle Clarendonian mollic Retallack, pers comm. 172

APPENDIX D3: MOLLIC HORIZON

Valentine 42.91 -100.48 11.49 Middle Clarendonian near- Retallack, pers comm. mollic Olcott Hill 42.17 -103.73 11.62 Middle Barstovian mollic Retallack, pers comm.

Norden quarry 42.79 -100.03 11.67 Middle Barstovian near- Retallack, pers comm. mollic Norden quarry 42.79 -100.03 11.68 Middle Barstovian near- Retallack, pers comm. mollic Norden quarry 42.79 -100.03 11.69 Middle Barstovian near- Retallack, pers comm. mollic Olcott Hill 42.17 -103.73 11.71 Middle Barstovian mollic Retallack, pers comm.

Broadwater 41.55 -102.72 12.96 Middle Barstovian non- Retallack, pers comm. mollic Broadwater 41.55 -102.72 13.07 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.05 Middle Barstovian near- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.06 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.07 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.08 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.09 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.10 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.10 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.12 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.12 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.13 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.14 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.14 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.15 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.16 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.16 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.17 Middle Barstovian non- Retallack, pers comm. mollic South Bijou Hill 43.49 -99.27 14.18 Middle Barstovian non- Retallack, pers comm. mollic 173

APPENDIX D3: MOLLIC HORIZON

Borchers 37.18 -100.37 2.00 Late Blancan near- Retallack, pers comm. Badlands north mollic Borchers 37.16 -100.37 2.12 Late Blancan near- Retallack, pers comm. Badlands south mollic Borchers 37.16 -100.37 2.23 Late Blancan mollic Retallack, pers comm. Badlands south Borchers 37.16 -100.37 2.23 Late Blancan mollic Retallack, pers comm. Badlands south Ainsworth 42.82 -100.56 2.25 Late Blancan near- Retallack, pers comm. mollic Ainsworth 42.63 -99.84 2.26 Late Blancan near- Retallack, pers comm. mollic Long Pine 42.65 -99.84 2.26 Late Blancan near- Retallack, pers comm. mollic Ainsworth 42.65 -99.84 2.27 Late Blancan near- Retallack, pers comm. mollic Borchers 37.16 -100.37 2.37 Late Blancan mollic Retallack, pers comm. Badlands south Ainsworth 42.68 -99.98 2.44 Late Blancan mollic Retallack, pers comm.

Borchers 37.16 -100.37 2.45 Late Blancan near- Retallack, pers comm. Badlands south mollic Ainsworth 42.68 -99.98 2.47 Late Blancan near- Retallack, pers comm. mollic Borchers 37.16 -100.37 2.50 Late Blancan mollic Retallack, pers comm. Badlands south Borchers 37.16 -100.37 2.54 Late Blancan near- Retallack, pers comm. Badlands south mollic Broadwater 41.60 -102.76 2.61 Late Blancan non- Retallack, pers comm. mollic Borchers 37.16 -100.37 2.62 Late Blancan non- Retallack, pers comm. Badlands south mollic Borchers 37.16 -100.37 2.64 Late Blancan non- Retallack, pers comm. Badlands south mollic Borchers 37.18 -100.37 2.65 Late Blancan non- Retallack, pers comm. Badlands north mollic Borchers 37.16 -100.37 2.73 Late Blancan non- Retallack, pers comm. Badlands south mollic Borchers 37.16 -100.37 2.81 Late Blancan non- Retallack, pers comm. Badlands south mollic Borchers 37.18 -100.37 2.84 Late Blancan non- Retallack, pers comm. Badlands north mollic Borchers 37.18 -100.37 3.04 Late Blancan non- Retallack, pers comm. Badlands north mollic Borchers 37.18 -100.37 3.27 Late Blancan non- Retallack, pers comm. Badlands north mollic Borchers 37.18 -100.37 3.38 Late Blancan mollic Retallack, pers comm. Badlands north Borchers 37.18 -100.37 3.45 Late Blancan mollic Retallack, pers comm. Badlands north 174

APPENDIX D3: MOLLIC HORIZON

Borchers 37.18 -100.37 3.56 Late Blancan mollic Retallack, pers comm. Badlands north Crooked Creek 37.18 -100.39 3.67 Late Blancan non- Retallack, pers comm. north mollic Broadwater 41.60 -102.76 3.76 Late Blancan non- Retallack, pers comm. mollic Crooked Creek 37.18 -100.39 3.82 Late Blancan non- Retallack, pers comm. north mollic Meade 37.22 -100.48 3.82 Late Blancan non- Retallack, pers comm. mollic Meade 37.22 -100.48 3.91 Late Blancan non- Retallack, pers comm. mollic Crooked Creek 37.18 -100.39 3.93 Late Blancan non- Retallack, pers comm. north mollic Meade 37.22 -100.48 4.00 Late Blancan non- Retallack, pers comm. mollic Crooked Creek 37.18 -100.39 4.05 Late Blancan non- Retallack, pers comm. north mollic Broadwater 41.60 -102.76 4.09 Late Blancan near- Retallack, pers comm. mollic Crooked Creek 37.18 -100.39 4.10 Late Blancan mollic Retallack, pers comm. north Meade 37.22 -100.48 4.10 Late Blancan non- Retallack, pers comm. mollic Meade 37.22 -100.48 4.17 Late Blancan non- Retallack, pers comm. mollic Meade 37.22 -100.48 4.23 Late Blancan non- Retallack, pers comm. mollic Crooked Creek 37.18 -100.39 4.27 Late Blancan mollic Retallack, pers comm. north Broadwater 41.60 -102.76 4.43 Late Blancan non- Retallack, pers comm. mollic Broadwater 41.60 -102.76 4.43 Late Blancan non- Retallack, pers comm. mollic Broadwater 41.60 -102.76 4.59 Late Blancan non- Retallack, pers comm. mollic Broadwater 41.60 -102.76 4.69 Late Blancan near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 4.97 Late Blancan non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.07 Late Blancan non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.12 Late Blancan non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.23 Late Blancan non- Retallack, pers comm. mollic Broadwater 41.60 -102.74 5.25 Late Blancan non- Retallack, pers comm. mollic Broadwater 41.60 -102.76 5.27 Late Blancan non- Retallack, pers comm. mollic 175

APPENDIX D3: MOLLIC HORIZON

Broadwater 41.60 -102.74 5.32 Late Blancan non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.35 Late Hemphillian non- Retallack, pers comm. mollic Lisco 41.52 -102.65 5.42 Late Hemphillian mollic Retallack, pers comm.

Harrisburg 41.50 -103.72 5.45 Late Hemphillian near- Retallack, pers comm. mollic Kimball 41.20 -103.65 5.45 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.46 Late Hemphillian mollic Retallack, pers comm.

Broadwater 41.60 -102.76 5.56 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.58 Late Hemphillian mollic Retallack, pers comm.

Broadwater 41.60 -102.76 5.59 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.66 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.71 Late Hemphillian non- Retallack, pers comm. mollic Almena 39.88 -99.69 5.71 Late Hemphillian mollic Retallack, pers comm.

Almena 39.88 -99.71 5.72 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.73 Late Hemphillian non- Retallack, pers comm. south mollic Broadwater 41.60 -102.74 5.75 Late Hemphillian near- Retallack, pers comm. mollic Almena 39.88 -99.71 5.75 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.75 Late Hemphillian non- Retallack, pers comm. south mollic Clayton 39.76 -100.09 5.76 Late Hemphillian near- Retallack, pers comm. mollic Almena 39.88 -99.69 5.77 Late Hemphillian mollic Retallack, pers comm.

Harrisburg 41.50 -103.72 5.78 Late Hemphillian non- Retallack, pers comm. mollic Kimball 41.21 -103.65 5.78 Late Hemphillian mollic Retallack, pers comm.

Clayton 39.76 -100.09 5.78 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.79 Late Hemphillian non- Retallack, pers comm. south mollic Almena 39.88 -99.71 5.80 Late Hemphillian mollic Retallack, pers comm.

Clayton 39.76 -100.09 5.81 Late Hemphillian near- Retallack, pers comm. mollic 176

APPENDIX D3: MOLLIC HORIZON

Crooked Creek 37.16 -100.39 5.81 Late Hemphillian non- Retallack, pers comm. south mollic Clayton 39.76 -100.09 5.84 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.84 Late Hemphillian near- Retallack, pers comm. south mollic Scott Lake 38.63 -100.81 5.84 Late Hemphillian non- Retallack, pers comm. mollic Almena 39.88 -99.71 5.84 Late Hemphillian mollic Retallack, pers comm.

Crooked Creek 37.16 -100.39 5.87 Late Hemphillian non- Retallack, pers comm. south mollic Clayton 39.76 -100.09 5.88 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.90 Late Hemphillian non- Retallack, pers comm. south mollic Clayton 39.76 -100.09 5.93 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 5.94 Late Hemphillian non- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.94 Late Hemphillian non- Retallack, pers comm. south mollic Clayton 39.76 -100.09 5.97 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 5.99 Late Hemphillian non- Retallack, pers comm. south mollic Hays 39.15 -99.28 6.00 Late Hemphillian near- Retallack, pers comm. mollic Crooked Creek 37.16 -100.39 6.04 Late Hemphillian non- Retallack, pers comm. south mollic Scott Lake 38.63 -100.81 6.04 Late Hemphillian non- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.09 Late Hemphillian near- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.10 Late Hemphillian mollic Retallack, pers comm.

Lisco 41.52 -102.65 6.17 Late Hemphillian mollic Retallack, pers comm.

Ogalalla 41.20 -101.66 6.21 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.27 Late Hemphillian non- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.30 Late Hemphillian mollic Retallack, pers comm.

Ellis 39.06 -99.57 6.34 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 6.34 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.40 Late Hemphillian non- Retallack, pers comm. mollic 177

APPENDIX D3: MOLLIC HORIZON

Broadwater 41.60 -102.74 6.41 Late Hemphillian near- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.46 Late Hemphillian mollic Retallack, pers comm.

Clayton 39.76 -100.09 6.50 Late Hemphillian mollic Retallack, pers comm.

Scott Lake 38.63 -100.81 6.50 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.05 -99.57 6.51 Late Hemphillian near- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.54 Late Hemphillian mollic Retallack, pers comm.

Harrisburg 41.50 -103.72 6.56 Late Hemphillian non- Retallack, pers comm. mollic Broadwater 41.60 -102.74 6.57 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.58 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.65 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.06 -99.57 6.68 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 6.68 Late Hemphillian non- Retallack, pers comm. mollic Hays, KS 39.15 -99.28 6.68 Late Hemphillian non- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.74 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.76 Late Hemphillian non- Retallack, pers comm. mollic Ogalalla 41.20 -101.66 6.76 Late Hemphillian near- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.77 Late Hemphillian near- Retallack, pers comm. mollic Clayton 39.76 -100.09 6.83 Late Hemphillian mollic Retallack, pers comm.

Scott Lake 38.63 -100.81 6.83 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 6.91 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.01 -99.57 7.02 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.13 -99.55 7.02 Late Hemphillian non- Retallack, pers comm. mollic Hays 39.01 -99.34 7.02 Late Hemphillian non- Retallack, pers comm. mollic Lisco 41.52 -102.65 7.03 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.06 Late Hemphillian non- Retallack, pers comm. mollic 178

APPENDIX D3: MOLLIC HORIZON

Hays 38.88 -99.46 7.07 Late Hemphillian non- Retallack, pers comm. mollic Hays 38.88 -99.46 7.12 Late Hemphillian non- Retallack, pers comm. mollic Ogalalla 41.20 -101.66 7.13 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.14 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.22 Late Hemphillian non- Retallack, pers comm. mollic Harrisburg 41.50 -103.72 7.22 Late Hemphillian near- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.32 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 7.36 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.42 Late Hemphillian non- Retallack, pers comm. mollic Scott Lake 38.63 -100.81 7.50 Late Hemphillian non- Retallack, pers comm. mollic Ash Hollow 41.29 -102.12 7.52 Late Hemphillian mollic Retallack, pers comm.

Ellis 39.01 -99.57 7.53 Late Hemphillian non- Retallack, pers comm. mollic Ogalalla 41.20 -101.66 7.59 Late Hemphillian near- Retallack, pers comm. mollic Ellis 39.04 -99.55 7.60 Late Hemphillian mollic Retallack, pers comm.

Scott Lake 38.63 -100.81 7.65 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 7.70 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 7.70 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.04 -99.53 7.70 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.13 -99.55 7.70 Late Hemphillian non- Retallack, pers comm. mollic Ellis 39.01 -99.57 7.70 Late Hemphillian non- Retallack, pers comm. mollic Ash Hollow 41.29 -102.12 7.92 Late Hemphillian non Retallack, pers comm. mollic Ellis 39.04 -99.55 8.04 Late Hemphillian mollic Retallack, pers comm.

Ash Hollow 41.29 -102.12 8.06 Late Hemphillian non Retallack, pers comm. mollic Lisco 41.52 -102.65 8.11 Late Hemphillian near- Retallack, pers comm. mollic Ellis 39.04 -99.53 8.38 Late Hemphillian mollic Retallack, pers comm. 179

APPENDIX D3: MOLLIC HORIZON

Ellis 39.01 -99.57 8.38 Late Hemphillian near- Retallack, pers comm. mollic 180

APPENDIX D4: VEGETATION

Location Name Latitude Longitude Age Time SliceNALMA Veg. Reference Marsland 42.69 -103.41 18.50 Early Hemingfordian 1 Axelrod 1985 UCMP PB99064d 42.43 -103.40 NA Early Hemingfordain 2 Stromberg 2004 UCMP PB99066t 42.43 -103.07 NA Early Hemingfordian 2 Stromberg 2004 UCMP PB99063a 42.43 -103.79 NA Early Arikareean 2 Stromberg 2004 UCMP PB99102 42.76 -103.92 NA Early Arikareean 2 Stromberg 2004 Pliohippus Draw 42.19 -103.77 NA Early Hemingfordian 2 Thomasson 1983 Thomasson 1991; Fox and Minimum Quarry 39.40 -100.10 9.55 Middle Clarendonian 2 Koch 2003 MacGinitie 1962; Axelrod Kilgore 42.80 -101.01 13-14 Middle Barstovian 2 1985 Beaver Co. 36.75 -100.48 11.00 Middle Clarendonian 0 Axelrod 1985 Clarendon 34.93 -100.88 11.00 Middle Clarendonian 3 Axelrod 1985 Gabel 1,3 43.08 -99.83 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 9a 43.08 -99.87 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 9b 43.08 -99.87 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 16 43.08 -101.72 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 17 43.13 -101.73 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 19 43.25 -99.43 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 21 43.17 -101.63 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 25-29 43.12 -101.72 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 30 43.12 -101.95 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 31-33 43.12 -102.02 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 34 43.07 -101.95 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 41 43.12 -101.70 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 46 43.07 -99.80 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 47-49 43.07 -99.80 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 50,51 43.12 -101.70 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 58 43.07 -99.85 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 59 43.12 -101.78 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 60 43.12 -102.00 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 61 42.80 -100.02 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 62 43.08 -99.83 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 63 42.78 -99.80 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 64 42.72 -99.77 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 65 42.80 -100.03 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 68 42.87 -100.53 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 69 42.98 -100.88 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 71 43.22 -101.27 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 80 42.85 -100.53 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 84 42.82 -101.72 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 87 42.88 -101.45 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 88 42.90 -101.43 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 89 42.78 -100.02 NA Middle Barstovian 3 Gabel et al. 1998 181

APPENDIX D4: VEGETATION

Gabel 90 42.67 -99.77 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 91 42.72 -99.78 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 104 42.68 -100.83 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 106a 42.68 -100.85 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 106b 42.68 -100.85 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 107 42.82 -100.93 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 124-126 42.68 -100.85 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 127 42.70 -100.85 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 128 42.82 -101.08 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 129 43.25 -99.38 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 144 42.90 -100.53 NA Middle Barstovian 3 Gabel et al. 1998 Gabel 155 42.65 -98.78 NA Middle Clarendonian 3 Gabel et al. 1998 Gabel 159, 160 42.53 -99.72 NA Middle Clarendonian 3 Gabel et al. 1998 Garden Co. 41.40 -102.35 NA Middle Clarendonian 2 Thomasson 1980

Poison Ivy Quarry 42.26 -98.07 10.00 Middle Clarendonian 2 Thomasson 1983, 1990 Tapir Hill 40.86 -104.00 13.00 Middle Barstovian 1 Wheeler 1977 Scout Canyon (Site 51b) 41.32 -102.16 NA Late Hemphillian 2 Thomasson 2005

Lemoyne Quarry (Site 54) 41.29 -101.88 11.30 Late Hemphillian 2 Thomasson 2005 Scott Lake (Site 106) 38.66 -100.90 NA Late Hemphillian 2 Thomasson 2005 Keller 39.04 -99.33 NA Late Hemphillian 2 Thomasson 2005 Russ's 41.32 -102.60 8.50 Late Hemphillian 4 Thomasson 1990 Minium 39.70 -101.14 8.00 Late Hemphillian 4 Thomasson 1990 Site 9 39.20 -99.75 7.75 Late Hemphillian 2 Thomasson 1990 Site 85 36.05 -100.68 7.50 Late Hemphillian 3 Thomasson 1990 Site 50/52 41.32 -102.14 NA Late Hemphillian 2 Thomasson 2005

182

APPENDIX D5: CROCODILE PRESENCE/ABSENCE

Location Name Latitude Longitude Bottom Age Top Age Time Crocodile Slice Rockyford district 43.20 -102.50 29.30 22.70 Early 0 Wounded Knee district (in part) 43.20 -102.50 29.30 22.70 Early 0 Black Bear Quarry 43.30 -100.90 19.83 16.53 Early 0 Flint Hill (Black Bear Quarries) 43.30 -100.90 19.83 16.53 Early 0 Porcupine South 43.30 -100.90 19.83 16.53 Early 0 Rosebud Formation (in part) sites 43.20 -101.40 22.70 19.77 Early 0 Wounded Knee District 43.20 -101.40 22.70 19.77 Early 0 Van Tassel South 43.00 -104.70 19.83 16.53 Early 0 Aletomeryx gracilis Quarry 42.70 -102.00 21.50 16.30 Early 1 Egelhoff Quarry; 1.6 km N of Niobrara 42.80 -99.70 16.53 11.76 Early River; Keya Paha County 0 Flattop Southwest 42.50 -104.60 29.30 22.70 Early 0 Roll Quarry - Guernsey South 42.50 -104.60 19.83 16.53 Early 0 Marsland; Dawes County 42.50 -103.30 19.83 16.53 Early 0 Harrison North 42.50 -103.50 29.30 22.70 Early 0 Rushville North 42.50 -102.50 29.30 22.70 Early 0 Box Butte County 42.40 -103.10 19.83 16.53 Early 0 Thomson Quarry; Sheep Creek-Snake 42.20 -103.80 17.87 16.53 Early Creek; Sioux County 0 Trojan Quarry; Sheep Creek-Snake 42.20 -103.80 16.53 14.73 Early Creek; Sioux County 1 East Surface Quarry; East Sinclair Draw 42.20 -103.80 16.53 14.73 Early 0 Joe Sanford Ranch (Mitchell North) 42.00 -103.70 29.30 22.70 Early 0 Goshen Hole district 41.90 -104.50 22.70 19.77 Early 0 Goshen Hole district 41.80 -104.50 29.30 22.70 Early 0 Agate Springs- Stenmylus Quarry-Harper 41.80 -103.40 22.70 19.77 Early Quarry 0 Harper Quarry 41.80 -103.40 22.70 19.77 Early 0 Harrison vicinity 41.80 -103.40 22.70 19.77 Early 0 Box Butte Members sites 41.80 -102.40 19.83 16.53 Early 0 Foley Quarry 41.80 -102.40 19.83 16.53 Early 0 Greenside Quarry 41.80 -102.40 19.83 16.53 Early 0 Hilltop Quarry 41.80 -102.40 19.83 16.53 Early 0 Long Quarry 41.80 -102.40 19.83 16.53 Early 0 Marsland Northwest 41.80 -102.40 19.83 16.53 Early 0 Ravine Quarry 41.80 -102.40 19.83 16.53 Early 0 Runningwater Formation sites 41.80 -102.40 19.83 16.53 Early 0 Sheep Creek Formation sites 41.80 -102.40 19.83 16.53 Early 0 Stonehouse Draw 41.80 -102.40 19.83 16.53 Early 0 Horse Creek Quarry; Laramie County 41.50 -104.70 19.83 17.87 Early 0 Bridgeport and Scotts Bluff area 41.50 -103.30 29.30 22.70 Early 0 Scotts Bluff Monument area 41.50 -103.30 29.30 22.70 Early 0 Albin Road 41.30 -104.50 29.30 22.70 Early 0 Broadwater district 41.30 -102.80 29.30 22.70 Early 0 183

APPENDIX D5: CROCODILE PRESENCE/ABSENCE

Bridgeport Quarries 41.20 -102.40 19.83 16.53 Early 0 Martin Quarry; Quarry A 40.40 -103.90 19.83 16.53 Early 0 Trojan Quarry; Sheep Creek-Snake 42.20 -103.80 16.53 14.73 Early Creek; Sioux County 1 East Surface Quarry; East Sinclair Draw 42.20 -103.80 16.53 14.73 Early 0 Myers Farm; near Red Cloud; Webster 40.10 -98.50 16.53 11.76 Middle County 0

South Bijou Hill; Charles Mix County 43.50 -99.10 16.53 11.76 Middle 0 Agate (near); Sioux County 42.40 -103.80 16.30 10.40 Middle 1 Egelhoff Site; Keya Paha County 42.80 -99.70 15.60 12.93 Middle 0 Railway Quarry A; 6.4 km of Valentine; 42.90 -100.50 12.93 11.67 Middle Cherry County 0

Norden Bridge Quarry; Brown County 42.80 -100.00 12.93 11.67 Middle 0 Olcott Hill; Sheep Creek-Snake Creek; 42.20 -103.80 11.76 9.04 Middle Sioux County 0

Norden Bridge Quarry; Brown County 42.80 -100.00 12.93 11.67 Middle 0 Middle branch of Verdigre Creek; Knox 42.60 -98.00 16.53 11.76 Middle County 1 NW1/4 sec23; T.33N.,R.3W.; Knox 42.70 -97.60 14.90 11.67 Middle County 1

Verdigree Quarry; Knox County 42.60 -98.00 16.53 8.28 Middle 1 SE1/4 SW1/4 SE1/4 sec.22,T.28N.,R ?W; 42.20 -98.10 11.76 8.28 Middle Antelope County 1

Lowell Hillman Ranch; near Wakeeney 39.00 -99.90 11.76 8.28 Middle 0 Egelhoff Quarry; 1.6 km N of Niobrara 42.80 -99.70 16.53 11.76 Middle River; Keya Paha County 0 Horse Creek Quarry (near); Laramie 41.50 -104.70 11.76 4.57 Middle County 0

Hottell Ranch; Banner County 41.50 -103.90 15.60 12.93 Middle 0 Egelhoff; Keya Paha County 42.80 -99.70 12.93 11.67 Middle 0 Kuhre Quarry; Brown County 42.40 -99.90 12.93 11.67 Middle 0 Big Spring Canyon; Bennett County 43.60 -100.90 11.76 8.28 Middle 0 Gate (6 miles south of) 36.90 -100.10 11.76 8.28 Middle 1 Barth Ranch 36.70 -101.00 11.76 8.28 Middle 1 Shannon Ranch; Donley County 35.10 -100.90 11.76 8.28 Middle 1 Bromley Ranch; Donley County 35.00 -100.80 11.76 8.28 Middle 0 Rowe Ranch; Donley County 35.10 -100.70 11.76 8.28 Middle 1 MacAdams Quarry; Donley County 35.10 -100.90 11.76 8.28 Middle 0 Noble Farr Ranch; Donley County 35.00 -100.80 11.76 8.28 Middle 0 Pine Ridge (near); Shannon County 43.00 -102.60 9.04 8.28 Middle 0 Olcott Hill; Sheep Creek-Snake Creek; 42.20 -103.80 11.76 9.04 Middle Sioux County 0 184

APPENDIX D5: CROCODILE PRESENCE/ABSENCE

Alligator Mefferdi Quarry; (George 42.60 -100.90 9.04 8.28 Middle Sawyer Ranch?) near Merritt Reservoir 1 Dam; Cherry County

SE1/4 SW1/4 SE1/4 sec.22,T.28N.,R ?W; 42.20 -98.10 11.76 8.28 Middle Antelope County 1

Buis Ranch; Beaver County 36.90 -100.20 6.41 4.98 Late 0 Axtel; Randall County 34.90 -101.70 6.41 4.98 Late 0 Christian Ranch; Armstrong County 34.90 -101.50 6.41 4.98 Late 0 Smart Ranch; Lubbock County 33.50 -101.60 6.20 4.60 Late 0 Wolf Canyon; Meade County 37.00 -100.60 6.41 4.98 Late 0 Devil's Nest Airstrip; Knox County 42.60 -97.90 6.41 4.98 Late 0 Saw Rock Canyon Fauna 37.00 -100.70 6.20 2.81 Late 0 Capps Neu Pratt Local Fauna; Ellis 36.10 -99.90 7.93 6.20 Late 0 County Port-of-Entry Pit = Arnett Local Fauna; 36.10 -99.90 7.93 6.20 Late Ellis County 0 Higgins Sebits Ranch Local Fauna; 36.10 -100.00 7.93 6.20 Late Lipscomb County 0

Box T Local Fauna; Lipscombe County 36.30 -100.10 7.31 6.41 Late 0 Optima (= Guymon); Texas County 36.80 -101.40 6.41 4.98 Late 1 Coffee Ranch (=Miami) Local Fauna; 13 35.70 -100.50 6.41 4.98 Late km NE of Miami; Hemphill County 0 Goodnight fauna; Mulberry Canyon; 35.00 -101.20 6.41 4.98 Late Charles Goodnight Ranch; Armstrong 0 County Terrell Christian Ranch; 15 km S and 12 34.90 -101.50 6.20 4.60 Late km W of Claude; Armstrong County 0 Axtel Local Fauna; east wall of Woody 34.90 -101.70 5.70 4.60 Late Draw; tributary of North Cita Canyon; C.5.6 km S & 19 km E of Canyon; 0 Randall County

Currie Ranch; Randall County 35.00 -101.70 6.20 4.60 Late 0 Jane's Quarry; E of Slaton; Crosby 33.40 -101.50 8.28 6.41 Late 0 County Hereford Dump; nr Hereford; Deaf Smith 34.80 -102.40 4.98 1.80 Late County 0

XI Ranch; Seward County 37.20 -100.80 5.20 3.40 Late 0 Holmes Pasture; Meade County 37.00 -100.50 5.20 2.81 Late 0 Burnett Quarry; Knox County 33.70 -99.70 1.80 0.39 Late 0 Ainsworth (near); Type area of Sand 42.60 -99.80 4.98 1.80 Late Draw Fauna; Brown County 0

Borchers; Meade County 37.30 -100.40 4.98 1.80 Late 0 Cita Canyon; Randall County 34.90 -101.70 4.98 1.80 Late 0 Lipscomb County 36.30 -100.30 5.20 3.40 Late 0 Saw Rock Canyon; Seward County 37.00 -100.70 4.98 1.80 Late 0 185

APPENDIX D5: CROCODILE PRESENCE/ABSENCE

Dockum (near); Dickens County 33.50 -100.80 5.20 1.64 Late 0 South Wichita River; Knox County 33.70 -99.70 1.80 0.39 Late 1 Crawfish Draw; 16km N of Crosbyton; 33.80 -101.20 4.98 1.80 Late Crosby County 1

Deer Park; Meade County 37.30 -100.40 4.98 1.80 Late 0 Holloman; Tillman County 34.50 -99.00 1.80 0.39 Late 0

186

APPENDIX E: PREDICTED SPECIES DISTRIBUTION MAPS

Species distribution maps for the middle and late time slice. Refer to Figure 5 for base map explanation and Figure 7 for predicted range explanation. 187

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