DOCSLIB.ORG

A Rodent Described from the Mathews Range, Central Kenya

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON 119(4):477-515. 2006. The status of Ototnys or estes dollmani Heller, 1912 (Muridae: Otomyinae), a rodent described from the Mathews Range, central Kenya Michael D. Carleton* and Ellen Schaefer Byrne (MDC) Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560-0108, U.S.A., e-mail: [email protected]; (ESB) 4209 Lawn Avenue, Western Springs, Illinois 60558, U.S.A. Abstract.•Morphological and morphometric comparisons of Otomys orestes dollmani, known only from Mount Gargues in the Mathews Range, central Kenya, indicate that the taxon is a valid species distinct from other African forms under which it has been previously synonymized (O. irroratus, O. orestes, O. tropicalis). Based also on these comparisons, the morphological recognition and distribution of O. orestes (including thomasi Osgood) are further clarified in relation to O. tropicalis (including elgonis Wroughton) in Kenyan mountains and O. typus proper in Ethiopian highlands; another taxon relegated to junior synonymy within O. typus, O. uzungwensis Lawrence and Loveridge from south-central Tanzania, is resurrected to species. Certain traditional characters used in Otomys taxonomy, in particular molar lamination, demonstrate conservative patterns of variation that complement spatial structure derived from morphometric analyses of craniometric data and that vindicate their continued utility in delimiting species. We argue that uncritical emphasis of polytypic species, applied following the biological species concept during the latter 1900s, has led to chronic underestimation of species diversity of Otomys confined to the Afromontane Biotic Region in eastern Africa, in particular those populations that inhabit afroalpine environments. Vlei or laminate-toothed rats of the Honacki et al. 1982, Corbet & Hill 1980, genus Otomys (Muroidea: Muridae) con- 1986, 1991; Musser & Carleton 1993). stitute a distinctive morphological and Musser & Carleton (2005) recently ac- phylogenetic radiation indigenous to the knowledged 23 species. In the most savannas and highlands within Subsa- considered revisionary study attempted haran Africa (Bohmann 1952, Carleton & to date, Bohmann (1952) recognized only Musser 1984, Watts & Baverstock 1995, 11 species, most of them containing from Ducroz et al. 2001, Taylor et al. 2004a). 3 to 5 well-marked subspecies and the Since the circumscription of the group as exceptionally polymorphic O. irroratus a suprageneric taxon (Otomyinae Thom- embracing 23 geographic races. Much of as, 1897), the number of Otomys {sensu the indecision over specific diversity has lato) considered to be valid species has involved populations distributed across vacillated greatly, ranging from 30 (Eller- eastern African mountains north of the man 1941) to as few as 8 (Petter 1982) but Zambezi River•from the Nyika Plateau usually around 12-14 (Misonne 1974, and Eastern Arc Mountains, through the ranges and volcanoes fronting the West- ern and Eastern Rift Valleys, to the * Corresponding author. Ethiopian Highlands. Within this region, 478 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON named forms have been variously and especially the last emerging M3. This inconsistently treated as subspecies of O. junction marks the border of the glossy irroratus, O. tropicalis, or O. typus. white enamel of the crown and dull white The present study focuses on one such cementum of the root and is visible as geographically localized population, Ot- a faint longitudinal line along the base of omys or es tes dollmani Heller (1912), de- the tooth (in lateral view). Those individ- scribed from Mount Gargues in the uals whose molars were incompletely Mathews Range, a small and relatively erupted, such that the line of the crown- low-elevation range lying to the north of root junction was visible on only the M1 Mount Kenya in central Kenya (Fig. 1). or Ml•2, were categorized as juveniles. Following its description, dollmani has Adult specimens were identified by the been sequentially referred to O. orestes visibility on all molars of the crown-root (Dollman 1915, Allen 1939, Ellerman line, which initiaUy appears approximate- 1941), O. irroratus (Bohmann 1952), or ly even with the maxillary alveoli (young O. tropicalis (Misonne 1974, Musser & adults); by this growth stage, the occlusal Carleton 1993). Early on, however. Hoh- surface of the molar row approximates lster (1919:148) had pointedly raised a horizontal plane. With advancing wear, dollmani to species until "actual inter- the crown-root line is progressively dis- grading specimens are found," a pragmat- placed above the plane of the maxillary ic viewpoint endorsed by Musser & bone, crown height is correspondingly Carleton (2005). Here, we consolidate diminished, and dentinal cores of the morphological and morphometric evi- individual laminae progressively expand dence that decidedly supports the last in width and length (full and old adults). interpretation. Our juvenile tooth-wear stage essentially concurs with age classes 1 and 2 as Materials and Methods defined by Taylor & Kumirai (2001), and the young, full, and old adult wear Specimens reported herein consist prin- stages to their age classes 3, 4, and 5, cipally of skins with their associated respectively. skulls and are contained in the following Specimens of Otomys, especially those North American museum collections: originating from older historically impor- Carnegie Museum of Natural History, tant surveys, complicate study of their Pittsburgh (CM); Field Museum of Nat- craniometric variation because a substan- ural History, Chicago (FMNH); Museum tial percentage of skulls encountered in of Comparative Zoology, Harvard Uni- museum collections are damaged. Com- versity (MCZ); and the National Museum monly, nasal bones are dislodged, zygo- of Natural History, Smithsonian Institu- matic arches broken, or the braincase tion, Washington D.C. (USNM, formerly fractured. Hence, we have taken a robust U.S. National Museum). approach to our definition of operational Relative age was crudely assessed for taxonomic units (OTUs), identifying an- every specimen examined based on tooth- alytical samples that correspond to moun- wear stages, employing a combination of tains or mountain ranges instead of single molar eruption and degree of molar localities and precise altitudes. Further, abrasion to identify four categories (juve- rather than eliminate those variables niles, young adult, full adult, old adult). taken on frequently broken cranial parts In view of the hypsodont molars charac- in order to amplify specimen numbers for teristic of Otomys, we used the appear- multivariate analyses, we have elected to ance of the basal crown-root junction to accept smaller sample sizes to capture gauge the degree of molar eruption. more fully size and shape differences. VOLUME 119, NUMBER 4 479 Cherangani jacksotíl^ ' íES (1891) • ' 1 ^ Ó ^ % ^ dollmani <%, • (1912) ^^x L'nubilus Mt Kenya \ '1-3' (1915) malleus f thomasi ^ * (1915) .¿^t (1910) troplcalis percivali (1902) tk (1915) •^ '--'"^ •^ • squalus ^•^ (1915) > 2500 m 2000-2500 m j 1500-200Öm Fig. 1. Mountainous region of eastern Africa inhabited by populations of Otoinys addressed herein, indicating type localities of relevant taxa and principal geographic features. Only length of rostrum, a measurement nomial species-group taxa of O. tropicalis that involves the nasal tips, was conven- are intended only to convey current tionally omitted in morphometric com- synonymy, not to denote any accepted parisons. subspecific classification. Full provenance Twelve OTUs, their two-letter abbrevia- and museum registration numbers are tions, and sample sizes of crania measured provided either in the Taxonomic Sum- were identified as follows. Provisional mary or in Appendix 1. Abbreviations are species taxonomy observes the arrange- used here and throughout the text for ment of Musser & Carleton (2005); tri- mount or mountains (Mt, Mts). 480 PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON Otomys dollmani: Kenya, Mt Cargues tween the lateral edge of the upper lobe of (MG, n = 6, including the holotype the exoccipital condyles; length of ros- USNM 181790). trum (LR), an oblique line measured from Otomys irroratus: South Africa, East- the posterior bevel of the right zygomatic ern Cape Province (EC, n = 21); Kwa- notch to the end of the nasal bones at Zulu-Natal Province (KZ, n = 17); their midsagittal junction; breadth of Western Cape Province (WC, n = 32). rostrum (BR), caliper points on the nasal Otomys orestes: Kenya, Aberdare Mts process of the premaxillaries just inside and Mt Kenya (OR, n =10). the dorsal zygomatic notch; postpalatal Otomys tropicalis elgonis: Kenya, Aber- length (PPL), from the anteriormost bevel dare Mts (AM, n = 24); Uasin Gishu of the mesopterygoid fossa to the mid- Plateau (UG, n = 7); Kaimosi and notch of the basioccipital; length of bony Kakamega (KA, n = 21); Kenya and palate (LBP), from the anteriormost bevel Uganda, Mt Elgon (ME, n = 19). of the mesopterygoid fossa to the poste- Otomys tropicalis tropicalis: Kenya, Mt rior end of the left incisive foramen; post Kenya (MK, n = 28). palatal breadth (PPB), distance across the Otomys typus: Ethiopia, all localities maxillary bones just behind the third (ET, n = 14). molars; length of incisive foramen (LIE), Otomys uzungwensis: Tanzania, Ud- greatest anterior-posterior expanse mea- zungwa Mts (UZ, n = 14). sured on the left side; length of diastema Sixteen
Recommended publications
  • Quaternary Murid Rodents of Timor Part I: New Material of Coryphomys Buehleri Schaub, 1937, and Description of a Second Species of the Genus

    Quaternary Murid Rodents of Timor Part I: New Material of Coryphomys Buehleri Schaub, 1937, and Description of a Second Species of the Genus

    QUATERNARY MURID RODENTS OF TIMOR PART I: NEW MATERIAL OF CORYPHOMYS BUEHLERI SCHAUB, 1937, AND DESCRIPTION OF A SECOND SPECIES OF THE GENUS K. P. APLIN Australian National Wildlife Collection, CSIRO Division of Sustainable Ecosystems, Canberra and Division of Vertebrate Zoology (Mammalogy) American Museum of Natural History ([email protected]) K. M. HELGEN Department of Vertebrate Zoology National Museum of Natural History Smithsonian Institution, Washington and Division of Vertebrate Zoology (Mammalogy) American Museum of Natural History ([email protected]) BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY Number 341, 80 pp., 21 figures, 4 tables Issued July 21, 2010 Copyright E American Museum of Natural History 2010 ISSN 0003-0090 CONTENTS Abstract.......................................................... 3 Introduction . ...................................................... 3 The environmental context ........................................... 5 Materialsandmethods.............................................. 7 Systematics....................................................... 11 Coryphomys Schaub, 1937 ........................................... 11 Coryphomys buehleri Schaub, 1937 . ................................... 12 Extended description of Coryphomys buehleri............................ 12 Coryphomys musseri, sp.nov.......................................... 25 Description.................................................... 26 Coryphomys, sp.indet.............................................. 34 Discussion . ....................................................
  • Karoo Bush Rat

    Karoo Bush Rat

    Otomys unisulcatus – Karoo Bush Rat threats that could cause widespread population decline. However, there are potentially synergistic effects of climate change drying up wetlands and overgrazing/ browsing removing at least part of the plant food and cover that this species relies upon. Such effects on subpopulation trends and population distribution should be monitored. Regional population effects: This species is endemic to the assessment region. Its dispersal abilities are not well known. Subpopulations seem to be patchily distributed at the landscape level, according to the presence of favourable habitats. While it is likely that movements and possibly rescue effects exist between subpopulations, Emmanuel Do Linh San others might be physically and genetically isolated. Regional Red List status (2016) Least Concern Distribution National Red List status (2004) Least Concern This species occurs throughout the semi-arid Succulent Reasons for change No change Karoo and Nama-Karoo of South Africa (Monadjem et al. 2015), specifically in the Eastern, Northern and Western Global Red List status (2016) Least Concern Cape provinces, with some limited occurrence in the TOPS listing (NEMBA) (2007) None Fynbos Biome (Vermeulen & Nel 1988; Figure 1). It may marginally occur in southern Namibia but further surveys CITES listing None are required to confirm this. Regardless, the bulk of the Endemic Yes population occurs in South Africa. Kerley and Erasmus (1992) argued that the lodges built by this species are In southern Africa the Karoo Bush Rat vulnerable to destruction by fire. As a result, they is the only rodent that constructs and occupies hypothesised that this shelter-building strategy is only large, dome-shaped stick nests or “lodges”, viable in the absence of frequent burning, and therefore it generally at the base of bushes.
  • Diversification of Muroid Rodents Driven by the Late Miocene Global Cooling Nelish Pradhan University of Vermont

    Diversification of Muroid Rodents Driven by the Late Miocene Global Cooling Nelish Pradhan University of Vermont

    University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2018 Diversification Of Muroid Rodents Driven By The Late Miocene Global Cooling Nelish Pradhan University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Part of the Biochemistry, Biophysics, and Structural Biology Commons, Evolution Commons, and the Zoology Commons Recommended Citation Pradhan, Nelish, "Diversification Of Muroid Rodents Driven By The Late Miocene Global Cooling" (2018). Graduate College Dissertations and Theses. 907. https://scholarworks.uvm.edu/graddis/907 This Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. DIVERSIFICATION OF MUROID RODENTS DRIVEN BY THE LATE MIOCENE GLOBAL COOLING A Dissertation Presented by Nelish Pradhan to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Specializing in Biology May, 2018 Defense Date: January 8, 2018 Dissertation Examination Committee: C. William Kilpatrick, Ph.D., Advisor David S. Barrington, Ph.D., Chairperson Ingi Agnarsson, Ph.D. Lori Stevens, Ph.D. Sara I. Helms Cahan, Ph.D. Cynthia J. Forehand, Ph.D., Dean of the Graduate College ABSTRACT Late Miocene, 8 to 6 million years ago (Ma), climatic changes brought about dramatic floral and faunal changes. Cooler and drier climates that prevailed in the Late Miocene led to expansion of grasslands and retreat of forests at a global scale.
  • Otomys Karoensis – Robert's Vlei

    Otomys Karoensis – Robert's Vlei

    Otomys karoensis – Robert’s Vlei Rat fynbos, predominantly on rocky slopes and dense fynbos patches, and this habitat is not prone to being overgrazed. However, the effects of climate change on this species should be monitored and, should molecular research reveal a species complex, it will necessitate a reassessment. Photograph Distribution wanted The species is endemic to South Africa and occurs in two disjunct regions, the fynbos of the Cape Fold Belt Mountains of the Western Cape as well as in the grasslands of southern Drakensberg in northern Eastern Cape and the central plateau grasslands of the southern Free State (Monadjem et al. 2015). It has been reported as occurring in Lesotho but this appears to have been a misidentification. Specifically, in the Eastern Cape, they Regional Red List status (2016) Least Concern* occur south of 32°S from King William’s Town in the east National Red List status (2004) Least Concern to Port Elizabeth in the west, possibly as far as Bredasdorp (Taylor 2013). In the Western Cape, it occurs Reasons for change No change in mountainous winter rainfall areas from the Cape Global Red List status (2016) Least Concern Peninsula to Citrusdal (Taylor 2013). It also occurs in summer rainfall areas of the southern areas of the TOPS listing (NEMBA) (2007) None Drakensberg range (north of 32°S and west of Lesotho) CITES listing None and into the Free State (Taylor 2013). The two disjunct populations in Western Cape and northern Eastern Cape Endemic Yes and Free State may be distinct species, although *Watch-list Data molecular and chromosomal data are currently lacking (Monadjem et al.
  • The Cryptic Case of Otomys Sloggetti (Sloggett's Vlei Rat)

    The Cryptic Case of Otomys Sloggetti (Sloggett's Vlei Rat)

    The cryptic case of Otomys sloggetti (Sloggett’s AUTHORS: Thalassa Matthews1 vlei rat): Interpreting murid molar morphology in Turid H. Nel2 the fossil record AFFILIATIONS: 1Centre of Excellence in Palaeosciences, Iziko Museums of South Africa, Cape Town, Vlei rats (Family: Muridae; Subfamily: Otomyinae) have a widespread distribution in southern Africa. They South Africa 2SFF Centre for Early Sapiens are favoured prey of barn and spotted eagle owls, and frequently become associated with archaeological Behaviour (SapienCE), University of deposits when the owls roost in cave sites. The phylogeny of several Otomyinae species is enigmatic, Bergen, Bergen, Norway and Otomys sloggetti (Sloggett’s vlei rat) is no exception. This species has been referred to as the ‘ice rat’ CORRESPONDENCE TO: and present distribution ranges are seemingly limited to mountainous areas, at high altitude, in Lesotho, Thalassa Matthews Drakensberg and the Karoo. It was thus surprising and unexpected when specimens closely resembling Otomys sloggetti (identification was based on molar morphology) were found in several archaeological EMAIL: sites on the south and west coasts of South Africa, and also in modern owl pellet assemblages – all [email protected] extralimital to the current reported distribution. However, further examination of and comparison between DATES: these specimens, as well as extensive differences observed between comparative Otomys sloggetti Received: 10 Sep. 2019 specimens from museum collections, highlighted potential problems associated with the common Revised: 01 June 2020 Accepted: 17 July 2020 practice of using tooth morphology to identify fossil murid species. We identified six molar morphotypes Published: 29 Jan. 2021 from the fossil and modern material, all of which bore a morphological resemblance to O.
  • An Integrated Phylogeographic Analysis of the Bantu Migration

    An Integrated Phylogeographic Analysis of the Bantu Migration

    AN INTEGRATED PHYLOGEOGRAPHIC ANALYSIS OF THE BANTU MIGRATION by Colby Tyler Ford A dissertation submitted to the faculty of The University of North Carolina at Charlotte in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Bioinformatics and Computational Biology Charlotte 2018 Approved by: Dr. Daniel Janies Dr. Xinghua Shi Dr. Anthony Fodor Dr. Mirsad Hadzikadic Dr. Matthew Parrow ii ©2018 Colby Tyler Ford ALL RIGHTS RESERVED iii ABSTRACT COLBY TYLER FORD. An Integrated Phylogeographic Analysis of the Bantu Migration. (Under the direction of DR. DANIEL JANIES) \Bantu" is a term used to describe lineages of people in around 600 different ethnic groups on the African continent ranging from modern-day Cameroon to South Africa. The migration of the Bantu people, which occurred around 3,000 years ago, was influ- ential in spreading culture, language, and genetic traits and helped to shape human diversity on the continent. Research in the 1970s was completed to geographically divide the Bantu languages into 16 zones now known as \Guthrie zones" [25]. Researchers have postulated the migratory pattern of the Bantu people by exam- ining cultural information, linguistic traits, or small genetic datasets. These studies offer differing results due to variations in the data type used. Here, an assessment of the Bantu migration is made using a large dataset of combined cultural data and genetic (Y-chromosomal and mitochondrial) data. One working hypothesis is that the Bantu expansion can be characterized by a primary split in lineages, which occurred early on and prior to the population spread- ing south through what is now called the Congolese forest (i.e.
  • The Role and Impact of Zootaxa in Mammalogy in Its First 20 Years

    The Role and Impact of Zootaxa in Mammalogy in Its First 20 Years

    Zootaxa 4979 (1): 070–094 ISSN 1175-5326 (print edition) https://www.mapress.com/j/zt/ Review ZOOTAXA Copyright © 2021 Magnolia Press ISSN 1175-5334 (online edition) https://doi.org/10.11646/zootaxa.4979.1.10 http://zoobank.org/urn:lsid:zoobank.org:pub:15620BC4-B989-4A98-84D0-019707FF0197 The role and impact of Zootaxa in mammalogy in its first 20 years PEDRO CORDEIRO-ESTRELA¹, ANDERSON FEIJÓ², PHILIPPE GAUBERT³, MARCELO WEKSLER4, LIONEL HAUTIER5,6, PAÚL M. VELAZCO7,8, PABLO TETA9, PIERRE-HENRI FABRE5,6, GERALDINE 10 11 VERON & JANET K. BRAUN 1Laboratório de Mamíferos, Departamento de Sistemática e Ecologia, Centro de Ciências Exatas e da Natureza, Universidade Federal da Paraíba, Campus I, João Pessoa, PB, Brazil. [email protected]; https://orcid.org/0000-0003-3383-571X 2Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Chaoyang District, Beijing, China. [email protected]; http://orcid.org/0000-0002-4643-2293 3Laboratoire Évolution & Diversité Biologique, Université Toulouse III Paul Sabatier, 118 route de Narbonne – Bât. 4R1, 31062 Toulouse cedex 9, France. [email protected]; https://orcid.org/0000-0002-1375-9935 4Departamento de Vertebrados, Museu Nacional, Universidade Federal do Rio de Janeiro, 20940-040 Rio de Janeiro, RJ, Brazil. [email protected]; https://orcid.org/0000-0001-8111-4779 5Institut des Sciences de l’Evolution (ISEM, UMR 5554 CNRS-IRD-UM), Université de Montpellier, Place E. Bataillon - CC 064 - 34095, Montpellier Cedex 5, France. [email protected]; https://orcid.org/0000-0001-8701-5421 [email protected]; https://orcid.org/0000-0002-3414-5625 6Mammal Section, Department of Life Sciences, The Natural History Museum, SW7 5DB London, United Kingdom 7Department of Mammalogy, American Museum of Natural History, Central Park West at 79th Street, New York, NY 10024, USA.
  • And Type the TITLE of YOUR WORK in All Caps

    And Type the TITLE of YOUR WORK in All Caps

    ECOLOGY OF THE SOUTHEASTERN POCKET GOPHER (GEOMYS PINETIS) IN SOUTHWESTERN GEORGIA by ASHLEY ERIN WARREN (Under the Direction of Steven B. Castleberry) ABSTRACT From September 2012 through December 2013 I used telemetry to investigate home range, survival, and movement patterns of southeastern pocket gophers (Geomys pinetis) in Southwestern Georgia. I also used a modeling approach to determine whether vegetation or soil characteristics best predicted gopher presence and developed a predictive model using combinations of vegetation and soil variables. Mean home range size of 17 gophers was 921.9 m2 (range = 43.4-2246.8 m2). Home range size was positively associated with body mass, percent silt, and soil carbon, and negatively associated with percent sand, percent clay, and grass ground cover. Two individuals were predated and survival rate was 0.78 over 51 weeks. Three individuals dispersed, with maximum dispersal distance of 319.1 m (range = 143.2-319.1 m). Pocket gophers exhibited greater activity at 00:00-4:00 and 16:00-20:00. Soil predicted presence better than vegetation, and the best predictive model combined percent clay, percent silt, pH, nitrogen, and carbon. INDEX WORDS: southeastern pocket gopher, Geomys pinetis, fossorial, burrows, tunnels, longleaf pine, Pinus palustris, home range, survival, dispersal, translocation, homing, telemetry, predation, Florida pine snake, Pituophis melanoleucus, ground cover, vegetation structure, soil texture, soil carbon, soil nitrogen, soil pH, habitat suitability, modeling, AIC ECOLOGY OF THE SOUTHEASTERN POCKET GOPHER (GEOMYS PINETIS) IN SOUTHWESTERN GEORGIA by ASHLEY ERIN WARREN B.S., The University of Southern Indiana, 2010 A Thesis Submitted to the Graduate Faculty of The University of Georgia in Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE ATHENS, GEORGIA 2014 © 2014 Ashley Erin Warren All Rights Reserved ECOLOGY OF THE SOUTHEASTERN POCKET GOPHER (GEOMYS PINETIS) IN SOUTHWESTERN GEORGIA by ASHLEY ERIN WARREN Major Professor: Steven B.
  • Phylogenetic Relationships and Divergence Times in Rodents Based on Both Genes and Fossils Ryan Norris University of Vermont

    Phylogenetic Relationships and Divergence Times in Rodents Based on Both Genes and Fossils Ryan Norris University of Vermont

    University of Vermont ScholarWorks @ UVM Graduate College Dissertations and Theses Dissertations and Theses 2009 Phylogenetic Relationships and Divergence Times in Rodents Based on Both Genes and Fossils Ryan Norris University of Vermont Follow this and additional works at: https://scholarworks.uvm.edu/graddis Recommended Citation Norris, Ryan, "Phylogenetic Relationships and Divergence Times in Rodents Based on Both Genes and Fossils" (2009). Graduate College Dissertations and Theses. 164. https://scholarworks.uvm.edu/graddis/164 This Dissertation is brought to you for free and open access by the Dissertations and Theses at ScholarWorks @ UVM. It has been accepted for inclusion in Graduate College Dissertations and Theses by an authorized administrator of ScholarWorks @ UVM. For more information, please contact [email protected]. PHYLOGENETIC RELATIONSHIPS AND DIVERGENCE TIMES IN RODENTS BASED ON BOTH GENES AND FOSSILS A Dissertation Presented by Ryan W. Norris to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy Specializing in Biology February, 2009 Accepted by the Faculty of the Graduate College, The University of Vermont, in partial fulfillment of the requirements for the degree of Doctor of Philosophy, specializing in Biology. Dissertation ~xaminationCommittee: w %amB( Advisor 6.William ~il~atrickph.~. Duane A. Schlitter, Ph.D. Chairperson Vice President for Research and Dean of Graduate Studies Date: October 24, 2008 Abstract Molecular and paleontological approaches have produced extremely different estimates for divergence times among orders of placental mammals and within rodents with molecular studies suggesting a much older date than fossils. We evaluated the conflict between the fossil record and molecular data and find a significant correlation between dates estimated by fossils and relative branch lengths, suggesting that molecular data agree with the fossil record regarding divergence times in rodents.
  • Comparative Renal Morphology of Some Southern African Otomyine Rodents

    Comparative Renal Morphology of Some Southern African Otomyine Rodents

    Acta Theriologica 39 (1): 37-48, 1994. PL ISSN 0001-7051 Comparative renal morphology of some southern African otomyine rodents Neville PILLAY, Ken WILLAN and Peter J. TAYLOR Pillay N., Willan K. and Taylor P. J. 1994. Comparative renal morphology of some southern African otomyine rodents. Acta theriol. 39: 37-48. The kidney structure of 21 individual otomyine rodents representing six southern African taxa from localities with differing climatic profiles was studied by means of light microscopy. Variation in the data was accounted for primarily by relative cortex and medulla proportions. The kidneys of Otomys angoniensis Wroughton, 1906, O. irroratus (Brants, 1827) and O. sloggetti robertsi Hewitt, 1927 displayed mesic adaptation, and those of O. unisulcatus F. Cuvier, 1829, Parotomys brantsii (A. Smith, 1834) and P. littledalei Thomas, 1918 xeric adaptation, reflecting species-specific pat- terns of geographic distribution across southern African rainfall gradients. Neither mesic nor xeric renal characters appear optimally expressed in the species considered, and it is postulated that feeding habits and behavioural adaptations play a significant role in the water economy of otomyine rodents. Department of Biology, University of Natal, King George V Avenue, Durban 4001 Republic of South Africa (NP, KW); Durban Natural Science Museum, P.O. Box 4085, Durban, 4000 Republic of South Africa (PJT) Key words: Otomyinae, renal morphology, climate, diet, behaviour Introduction The physiology and anatomy of the mammalian kidney have been comparatively well studied, although more attention has been paid to arid adapted than to mesically adapted species (inter alia Sperber 1944, Schmidt-Nielsen 1964, MacMillen and Lee 1969, Marsh et al.
  • Inbreeding in Littledale's Whistling Rat Parotomys Littledalei

    Inbreeding in Littledale's Whistling Rat Parotomys Littledalei

    JOURNAL OF EXPERIMENTAL ZOOLOGY 293:171–178 (2002) Inbreeding in Littledale’s Whistling Rat Parotomys littledalei NEVILLE PILLAY Ecophysiological Studies Research Group, School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, WITS 2050, South Africa ABSTRACT Despite its rarity in nature, inbreeding is sometimes evident in species occupying ephemeral, unpredictable habitats, and which occur at low densities. One such species is Littledale’s whistling rat, Parotomys littledalei, a murid rodent endemic to the south-west arid region of South Africa. Using a captive population of P. littledalei, I studied mate choice for kin and nonkin, and the reproductive performance of inbred and outbred pairs. In choice tests, estrous females presented with either odors or actual males showed a preference for siblings or half-siblings to unrelated males. Males did not discriminate between the odor of estrous kin and nonkin. In breeding studies, inbred (mother-son; brother-sister) and outbred (proven female and an unrelated young male and nonsiblings) pairs had a similar reproductive output, although the sex ratio favored males in inbred litters. The development of inbred young was indistinguishable from outbred young. The results indicate that female P. littledalei prefer to inbreed, but there are no apparent advantages to inbreeding over outbreeding. J. Exp. Zool. 293:171–178, 2002. r 2002 Wiley-Liss, Inc. Inbreeding is generally regarded as being disruption of gene complexes (Partridge, ’83; disadvantageous, particularly when mating occurs Shields, ’93). between close relatives, such as between parents Ecologically, inbreeding is apparently more and offspring and siblings (Clutton-Brock and common in populations occupying ephemeral, Harvey, ’76).
  • Genetic Structuring, Dispersal and Taxonomy of the High-Alpine Populations of the Geranium Arabicum/Kilimandscharicum Complex in Tropical Eastern Africa

    Genetic Structuring, Dispersal and Taxonomy of the High-Alpine Populations of the Geranium Arabicum/Kilimandscharicum Complex in Tropical Eastern Africa

    RESEARCH ARTICLE Genetic structuring, dispersal and taxonomy of the high-alpine populations of the Geranium arabicum/kilimandscharicum complex in tropical eastern Africa Tigist Wondimu1,2*, Abel Gizaw1,2, Felly M. Tusiime2,3, Catherine A. Masao2,4, Ahmed A. Abdi2,5, Yan Hou2, Sileshi Nemomissa1, Christian Brochmann2 1 Department of Plant Biology & Biodiversity Management, College of Natural Sciences, Addis Ababa a1111111111 University, Addis Ababa, Ethiopia, 2 Natural History Museum, University of Oslo, Blindern, Oslo, Norway, a1111111111 3 Department of Forestry and Tourism, School of Forestry, Geographical and Environmental Sciences, a1111111111 Makerere University, Kampala, Uganda, 4 University of Dar es Salaam, Institute of Resource Assessment, a1111111111 Dar es Salaam, Tanzania, 5 National Museums of Kenya, Nairobi, Kenya a1111111111 * [email protected], [email protected] Abstract OPEN ACCESS The scattered eastern African high mountains harbor a renowned and highly endemic flora, Citation: Wondimu T, Gizaw A, Tusiime FM, Masao but the taxonomy and phylogeographic history of many plant groups are still insufficiently CA, Abdi AA, Hou Y, et al. (2017) Genetic structuring, dispersal and taxonomy of the high- known. The high-alpine populations of the Geranium arabicum/kilimandscharicum complex alpine populations of the Geranium arabicum/ present intricate morphological variation and have recently been suggested to comprise two kilimandscharicum complex in tropical eastern new endemic taxa. Here we aim to contribute to a clarification of the taxonomy of these pop- Africa. PLoS ONE 12(5): e0178208. https://doi.org/ 10.1371/journal.pone.0178208 ulations by analyzing genetic (AFLP) variation in range-wide high-alpine samples, and we address whether hybridization has contributed to taxonomic problems.