Applying Taxonomy to Wildlife Research and Management Module Overview

TheThe SpeciesSpecies QuestionQuestion

ApplyingApplying TaxonomyTaxonomy ToTo WildlifeWildlife ResearchResearch AndAnd ManagementManagement

September 1, 2006

Dear Educator,

Colorado has long been committed to the conservation of all wildlife species, whether hunted, or fished, or viewed. One of the nation’s great wildlife restoration success stories—the American Peregrine Falcon—had its beginnings here in the early 1970’s. A Colorado biologist rappelled over cliffs more than 500 feet high, dangled from a thin rope and dodged swooping Peregrines to retrieve their DDT-thinned eggs. He tucked them into his vest and made all-night drives across the state for artificial incubation and hatching. Other successes, such as the restoration and recovery of prairie grouse, lynx, river otter and a number of native fishes, also have their roots in the efforts of Colorado Division of Wildlife professionals.

Science-based management decisions are essential to securing species at risk, as well as conserving all the state’s wildlife species. The numbers of scientific disciplines that influence and inform wildlife management are staggering. Advances in taxonomy and molecular biology, in particular, have affected how biologists think about and identify species and subspecies. We invite you and your students to explore new developments in the frontiers of science with us as we harness innovative technologies and ideas and use them to maintain healthy, diverse and abundant wildlife.

Sincerely,

Bruce L. McCloskey Director Acknowledgments

Funding for this project was provided by US Fish & Wildlife Service Wildlife Conservation and Restoration Program Grant No. R-11-1, Great Outdoors Colorado Trust Fund (GOCO), and the sportsmen of Colorado.

The Colorado Division of Wildlife gratefully acknowledges the following individuals:

For content advice and critical review: Field-test Educators (cont.): Dr. David M. Armstrong, University of Colorado Jeff Keidel, Buena Vista High School, at Boulder, Department of Ecology and Buena Vista, CO Evolutionary Biology Matt Landis, North Park High School, Walden, CO For assistance in developing the field test: Robert Lancaster, Walsh High School, Walsh, CO Nicole Knapp, Science Educator, BSCS Mark Little, Broomfield High School, Broomfield, Anne Tweed, Senior Science Consultant, McREL CO (Mid-continent Research for Education and Rick Moeller, Mountain View High School, Learning) Loveland, CO Pam Van Scotter, Director, BSCS (Biological Lyn Neve, Swink High School, Swink, CO Sciences Curriculum Study) Center for Curriculum Development Dorothy Schnabel, Granada Undivided High School, Granada, CO Field-test Educators: Jill Smith, McClave High School, McClave, CO Shelley Harwell, Heritage High School, Debbie Yeager, Moffat County High School, Littleton, CO Craig, CO

Content Advisors and Reviewers: Graphic Design: Writers: Lisa Evans, Northeast Region Darren Eurich, State of Colorado Wendy Hanophy, DOW Education Coordinator, DOW Integrated Document Solutions (IDS) Larry Ann Ott, Retired Educator, Leigh Gillette, Southwest Region Adams County School District 12, Education Coordinator, DOW Illustrations: Colorado Linda Groat, Southeast Region Rural Helen Zane Jensen, Sage Grouse and Education Specialist, DOW Sage Grouse anatomy illustrations on Copy Editor: pages 22 and 24 Renee Herring, Wildlife Watch Tim Pollard, Colorado Department of Coordinator, DOW Marjorie Leggitt, All Other Illustrations Natural Resources Stan Johnson, Northwest Region Education Coordinator, DOW Classroom Observations and Educator Printing: Debbie Lerch-Cushman, Metro Denver Interviews: State of Colorado Integrated Education Coordinator, DOW Wendy Hanophy, DOW Document Solutions (IDS) Print Steve Lucero, Southeast Region Operations James Phillips Education Coordinator, DOW Tabbi Kinion, Project WILD Administrative Assistance: ©Copyright 2006 by Colorado Division of Wildlife. All rights Coordinator, DOW reserved. Permission granted to reproduce handouts for Ken Morgan, Private Lands Habitat Emily Wiseman classroom use. All illustrations are copyright by the artists Specialist, DOW and may not be reproduced or transmitted in any form or by any means, electronic or mechanical, or by any infor- Jeff Rucks, Head of Education, DOW Project Coordinator and Editor: mation storage or retrieval system, without permission in writing. For permissions and other rights under this Gary Skiba, Senior Wildlife Wendy Hanophy, DOW copyright, please contact Colorado Division of Wildlife, Conservation Biologist Supervisor, 6060 Broadway, Denver, CO 80216, Attn: Wendy Hanophy. Southwest Region, DOW TableTable OfOf ContentsContents The Species Question Applying Taxonomy To Wildlife Research And Management Module Overview ...... 1

Lesson 1: The Species Question Educator’s Overview...... 6 The Species Question ...... 10

Lesson 2: Birds Of A Feather Educator’s Overview...... 16 Birds Of A Feather ...... 20 A Closer Look...... 21 Hidden In Plain View...... 26

Lesson 3: Taxonomy Through The Ages Educator’s Overview...... 28 Taxonomy Through The Ages. . . . 41

Lesson 4: Understanding Ungulate Phylogeny Educator’s Overview...... 52 Understanding Ungulate Phylogeny ...... 56 TableTable OfOf ContentsContents Lesson 5: The Pocket Gopher Cladogram Conundrum Educator’s Overview...... 64 Pocket Gophers Of Colorado. . . . 68 Characters Of Colorado Pocket Gophers ...... 69 The Pocket Gopher Cladogram Conundrum ...... 70

Lesson 6: Déjà Vu Educator’s Overview...... 80 Déjà Vu ...... 84

Glossary ...... 95 Module Overview The Species Question Applying Taxonomy To Wildlife Research And Management

Taxonomy— each state’s wildlife management options are restricted by a species status. Some species It’s Not Just for Geeks Anymore! management falls under the purview of the Federal government. Taxonomy is the science-based hierar- chical classification of the world’s species. Now that taxonomy can literally hit Over the centuries, taxonomy has been used somebody “where they live,” the ideas and to organize, interpret, and understand the methods of delineating species have become diversity of life on Earth. everyone’s business. While no conscientious person would seek to propel a fellow creature As a science, taxonomy had traditionally into the long night of extinction, few would been viewed as an obscure discipline want to limit what they could do with their involving brainy professors and highbrow property or their life without good evidence science know-it-alls who would memorize and that it really mattered to a species’ survival. interpret thousands of Latin species names. Few paid attention to advances in the field or It turns out that sometimes hard evidence to the many scathing disputes between taxon- is slow in coming. Many of the ideas omists. A decision to place an organism in the scientists hold about species, including the genus Spea rather than Scaphiopus would not concept of species itself, are undergoing make the front page of the newspaper, or revision. With advances in molecular biology, even the back page for that matter. Educators we find that some animals that look alike are such as yourself would cruise through the in no way related. Contrarily, some that look taxonomy section of the textbook as quickly different have nearly identical genetics! For as possible, and move on to more vital topics. students (or anyone, for that matter) used to In a word, taxonomy was BORING. clean, clear-cut answers, this module on taxonomy and systematics might be Public and academic indifference to “annoying.” Each concept of species has its taxonomy was lost forever when precise deficiencies, so modern-day biologists rely on taxonomic recognition of species and legal definitions and agreed upon subspecies came to be the basis for conventions. They employ techniques of protection under the Endangered Species Act cladistics and evolutionary systematics to (ESA). Signed into law by President Richard determine both the relatedness of organisms Nixon in 1973, the law is considered one of and their potential for a unique evolutionary the most stringent environmental protection future. Once viewed as a “stagnant” documents ever enacted. The penalties are science—taxonomy is exciting and chal- stiff. Anyone found to take, harass, harm, lenging. As you and your students join us in pursue, hunt, shoot, wound, kill, trap, capture, our discoveries, our questions, and our or collect a listed species could receive jail arguments, you will develop a clearer under- terms and large fines. The ESA also impacts standing of the nature of scientific knowledge land use decisions, which can in turn impact and the scientific process, the human Module Overview individuals, families, communities and dimension of science, and the value of peer economies in unforeseen ways. In addition, review.

The Species Question 1 What is This? Stan Johnson, Education Coordinator, NW Region This six-lesson module, designed for 711 Independent Avenue almost two weeks of classroom instruction, Grand Junction, CO 81505 begins with basic high school level taxonomy 970-255-6191 and classification, and then introduces the larger field of systematics. The module is Linda Groat, Rural Education Specialist designed to supplement or replace the SE Region activities found in most high school biology 2500 S. Main textbooks that address these topics. It is the Lamar, CO 81502 second module developed by the DOW to 719-336-6608 address the specific learning objectives of high school students. Materials are inquiry Steve Lucero, Education Coordinator, based, develop critical thinking skills, supply SE Region evidence to support each concept, and 4255 Sinton Road include real data from recent research Colorado Springs, CO 80907 projects. The last two lessons also emphasize 719-227-5203 the ethical tradition of scientists; the value of peer review, truthful reporting about methods Lisa Evans, Education Coordinator, and outcomes of investigations, and making NE Region public the results of scientific work. 317 W. Prospect Fort Collins, CO 80526 970-472-4343

Debbie Lerch-Cushman, Education Using The Species Question: Coordinator, Applying Taxonomy To Wildlife Denver Metro Area 6060 Broadway Research And Management in Your Denver, CO 80216 Classroom 303-291-7328 The lessons in this module are designed to be taught in sequence. For each activity, the students take on the role of a wildlife biologist, receive an introduction to the Correlation to the Colorado Model problem and to their task, and choose and Content Standards analyze relevant information. The Species Question: Applying Taxonomy There are DOW Education Coordinators To Wildlife Research And Management throughout the state that may be able to supports teachers in their efforts to provide provide additional materials, such as sage the knowledge and skills specified in the grouse wings, to supplement these lessons or Colorado Model Content Standards and the to provide resources on other biology topics. corresponding grade level assessment Feel free to contact your Education frameworks. Coordinator at any time—they would love to hear from you:

Leigh Gillette, Education Coordinator, SW Region 415 Turner Drive Durango, CO 81303 970-375-6709

Module Overview

2 The Species Question COLORADO MODEL CONTENT STANDARDS Lesson 3: Lesson 4: Lesson 5: Lesson 1: Lesson 2: Taxonomy Understanding The Pocket Lesson 6: The Species Birds Of A Through Ungulate Gopher Cladogram Déjà Vu Question Feather Science The Ages Phylogeny Conundrum 1: Students understand the processes of scientific XXXX investigation and design. They conduct, communicate about and evaluate such investigations.

3.1: Students know and understand the characteristics XXXXXX of living things, the diversity of life, and how living things interact with each other and with their environment.

3.3: Students know and understand how the human XXXX body functions, factors that influence its structures and functions, and how these structures and functions compare with those of other organisms.

5: Students know and understand interrelations among XXXX science, technology, and human activity and how they can affect the world.

6: Students understand that science involves a XXXXXX particular way of knowing and understand common connections among scientific disciplines.

COLORADO MODEL CONTENT STANDARDS Lesson 3: Lesson 4: Lesson 5: Lesson 1: Lesson 2: Taxonomy Understanding The Pocket Lesson 6: The Species Birds Of A Through Ungulate Gopher Cladogram Déjà Vu Question Feather Reading and Writing The Ages Phylogeny Conundrum 1: Students read and understand a variety of materials. XXXXXX

2: Students write and speak for a variety of purposes XX X and audiences.

3: Students write and speak using conventional XXXXXX grammar, usage, sentence structure, punctuation, capitalization, and spelling.

4: Students apply thinking skills to their reading, XXXXXX writing, speaking, listening, and viewing.

5: Students read to locate, select, and make use of XX X relevant information from a variety of media, reference,

and technological sources. Module Overview

The Species Question 3 COLORADO MODEL CONTENT STANDARDS Lesson 3: Lesson 4: Lesson 5: Lesson 1: Lesson 2: Taxonomy Understanding The Pocket Lesson 6: The Species Birds Of A Through Ungulate Gopher Cladogram Déjà Vu Question Feather Mathematics The Ages Phylogeny Conundrum 1: Students develop number sense and use numbers X and number relationships in problem-solving situations and communicate the reasoning used in solving these problems.

3: Students use data collections and analysis, statistics, X and probability in problem-solving situations and communicate the reasoning used in solving these problems.

COLORADO MODEL CONTENT STANDARDS Lesson 3: Lesson 4: Lesson 5: Lesson 1: Lesson 2: Taxonomy Understanding The Pocket Lesson 6: The Species Birds Of A Through Ungulate Gopher Cladogram Déjà Vu Question Feather Geography The Ages Phylogeny Conundrum 2: Students know the physical and human X characteristics of places, and use this knowledge to define and study regions and their patterns of change.

3: Students understand how physical processes shape XXX Earth’s surface patterns and systems.

5: Students understand the effects of XX X interactions between human and physical systems and the changes in meaning, use and importance of resources.

6: Students apply knowledge of people, places, and X X X X environments to understand the past and present and to plan for the future.

Module Overview

4 The Species Question Notes ______Module Overview ______

The Species Question 5 Lesson 1 Educator’s Overview The Species Question

Summary Students read an article, then discuss and evaluate the Duration strengths and weaknesses of several species concepts. They then discuss the consequences of conflicting definitions on One 45-minute class period a state wildlife agency’s ability to conserve species and the ecosystems upon which they depend.

Vocabulary Learning Objectives (or trinomial) nomenclature or in Biodiversity everyday vernacular. Something After completing this activity, is a dog, a cat, or a turtle. Clones students will be able to: Distinct Population Traditionally, people relied Segment (DPS) • Identify the strengths and on observations of anatomical weaknesses of the species Endangered differences and breeding definition used in their behavior to distinguish species. Hybrid textbook. Before Darwin, species were Morphological • Compare various species thought to represent independent Niche concepts and make a note of acts of creation, and were considered immutable. A century Reproductive the variety of characteristics and a half later, with the arrival isolation (physical, molecular, of evolution theory, the discovery Species Concepts geographical, ecological, and of genes and the advances in • Biological so on) that biologists use to microbiological research— species concept identify organisms. including DNA analysis—a great • Ecological deal of knowledge about the species concept • Make a case for the • Isolation species necessity of a legal definition differences and similarities concept of species for wildlife between organisms has become available. Species evolve—they • Morphological managers. species concept change over time. Species concepts also evolve; and the Subspecies scientific community seems to Threatened have more disagreement about Wildlife Background what constitutes a species now than ever before. Wildlife management In biology, a species is the basic unit of biodiversity. It often It may come as a shock to corresponds to the way people your students to discover that identify different kinds of there is no commonly accepted organisms. We “name” living definition of what a species things using this concept, either is. While the class textbook with standard scientific binomial probably contains some version

Lesson 1: The Species Question

6 The Species Question of the biological species concept ronment but do not interbreed, that has predominated secondary while others look very different texts over the past 60 years, that and live in radically different definition has some serious environments yet can drawbacks. The textbook defi- interbreed and produce fertile nition provides a starting place offspring, and so on. for students to study the variety of life, but it is important for 4. Discuss the various species educators to emphasize that it is concepts in terms of the simply one of many species scientific process. Why is the concepts. Definitions are a lot definition of species being like hypotheses—scientists must disputed? New information continually test their usefulness about genetics and evolution in the light of new information. has caused scientists to reevaluate their ideas about For wildlife professionals and living organisms. other scientists tasked with preserving the variety of life on 5. Why is a legal definition of earth, the species question is species needed? Wildlife important. Some working defi- managers and others must nition of species is needed to make decisions and take Materials and frame and implement biological actions to maintain healthy Preparation laws—such as the Endangered populations of organisms and Species Act. • Student Reading their habitats. In order to avoid Pages for confusion and possibly court The Species battles, they need to agree on Question—one what populations need photocopy per student Teaching Strategies protection. • Access to biology 1. Thoroughly read the textbook and student materials for The internet Species Question. 2. Give each student the first Assessment reading packet, The Species Students’ comparison of Question. their textbooks’ species defi- 3. After giving students nition with the characteristics sufficient time to read the used by wildlife biologists to packet, discuss the many determine species serves as species concepts as a class. an assessment for this activity. What are some of the reasons that there is little agreement on species concepts? There are huge differences among the Lesson 1: The Species Question kinds of organisms; organisms have different kinds of reproduction (sexual or asexual), some organisms look similar and live in the same envi-

The Species Question 7 Extensions Key • Students could read and evaluate the 1. How many different definitions of Policy Regarding the Recognition of species did you find? Answer varies Distinct Vertebrate Population under the 2. List at least three other species Endangered Species Act. The document concepts that you found: Answers will can be found at: vary, but some of the other species http://www.fws.gov/endangered/ concepts are Recognition, Evolutionary, federalregister/1996/p960207c.pdf. Phylogenetic, Diagnosability, Cohesion, There was considerable national debate Genealogical, Cladistic, and Pluralistic. during the drafting and public comment 3. What is your biology textbook’s defi- period of this document. The recommen- nition of species? Answer varies dations and criticisms are summarized 4. Does the textbook definition share any and addressed by the Department of the of the characteristics used to determine a Interior. After students read these distinct population segment? If so, which arguments, do they agree or disagree ones? Answer varies with the responses? 5. Why is a legal definition of species necessary? State and federal laws require that wildlife agencies protect wildlife species and biodiversity. There needs to be a clear and consistent way to determine whether an organism is a species so that the organism can be managed appropriately.

Lesson 1: The Species Question

8 The Species Question Notes ______

______Lesson 1: The Species Question ______

The Species Question 9 Lesson 1 Student Pages The Species Question

“It is the policy of the state of Colorado that the wildlife and their environment are to be protected, preserved, enhanced and managed for the use, benefit, and enjoyment of the people of this state and its visitors.” —Colorado Revised Statutes 33-1-101 (1)

The Colorado Division of Wildlife Biologists at the DOW also abide (DOW) is the state agency responsible for by federal wildlife laws. One of the protecting and managing wildlife and most important of these laws is the habitat, and providing wildlife related Endangered Species Act (ESA) of 1973 recreation. The DOW employs trained biol- that protects plants and animals from ogists and other specialists to “manage” becoming extinct in this country. Under wildlife—to use scientific knowledge to the ESA, species may be listed as either maintain healthy populations of wildlife “endangered” or “threatened.” and its habitat and preserve biodiversity. Endangered means a species is in danger Wildlife includes all non-domestic of extinction throughout all or a significant mammals, birds, fish, amphibians, reptiles, portion of its range. Threatened means a mollusks, and crustaceans that occur species is likely to become endangered within the boundaries of the state. within the near future throughout all or a Biodiversity is short for biological significant portion of its range. diversity. It includes the variety of species, the genetic differences within species, and the variety of ecosystems in the state. What is a Species?

Kingfisher Before a species can be managed and protected, it must be identified. Unfortunately, what might seem to be the simplest task in biology can be one of the most baffling. What is a species? You would think that the question would have

Lesson 1: The Species Question

10 The Species Question been answered ages ago, but it crops up Then there is the ecological species repeatedly in many different circum- concept, which defines a species by its stances. As experts try to create defi- niche or ecological role—the set of nitions of species to apply to the various resources it consumes and habitats it types organisms that they are studying, occupies. This definition might work well each seems to have its shortcomings. for an organism such as an Abert’s squirrel, which only lives in ponderosa One of the oldest methods for iden- pine forests and only eats ponderosa pine tifying species is to group organisms that nuts. It is a bit more challenging to apply are similar to each other in appearance to a coyote, which lives in nearly every and behavior. This is the morphological part of the state and eats virtually or phenetic species concept, where anything. Would a coyote living in a organisms with similar physical traits are spruce/fir forest eating red squirrels be a lumped together as species. Using this different species than a coyote living in the definition, Chihuahuas, Saint Bernards, grasslands eating rabbits? Pugs, and German Shepherds could all be different species. So could Shetland ponies, Clydesdales and Thoroughbreds. Dog Gone It! One of the more widely accepted definitions—and possibly the one found in your biology textbook—says a species is a group of organisms that are genetically similar enough to breed and produce viable and fertile offspring. This biological species concept seems simple enough, and seems to incorporate both the morphological and ecological species concepts. After all, if organisms are able to breed, they must have similar characteristics, behavior and ecology.

Abert’s

Squirrel Lesson 1: The Species Question Coyote

The Species Question 11 Looking at different canines, we find and produce fertile offspring. Given that all that even this definition has its problems. the wild canines mentioned can potentially For example, pugs do not look like interbreed with domestic dogs like the wolves, coyotes, jackals, or dingos. Pugs pug, are they all one species? often occupy the plush chair in the living room, while wolves are adapted to forests, It gets even more complicated. jackals to dry grasslands in Africa and so Coyotes and wolves can and do on. Nevertheless, given the opportunity, interbreed in areas where their ranges pugs can interbreed with all these species overlap, but only female coyotes mate with male wolves and their offspring only breed with wolves. What prevents male coyotes from mating with female wolves? Pug Moreover, in Africa, where there are several different types of jackal sharing the same habitat, they completely ignore each other. If mated under artificial conditions, these jackals can produce fertile offspring.

Wolf

Lesson 1: The Species Question

12 The Species Question Cats Too! His isolation species concept defined a species as groups of interbreeding natural This problem is not just limited to populations that are reproductively canines. Lions and tigers normally do not isolated from other such groups. share the same habitat. Lions live on the Reproductive isolation means that a African savannah (grasslands) and tigers population of animals cannot mate with inhabit the jungles of Asia. However, when another population of animals due to they are placed together in zoos, they some barrier or factor such as: court, mate, and produce fertile tigons and • Differences in behavior ligers. • Physical or geographical barriers

One noted zoologist attempted to • Incompatible mating structures address this issue by changing the definition of a species slightly. Because reproductive isolation is not always complete, some animals—such as the canines and felines already mentioned—can Tiger produce fertile offspring when in contact with one another. Others, such as the horse and the donkey, can produce a healthy offspring—a mule—that is infertile. As another working definition, the fertile or infertile offspring of normally isolated populations are called hybrids.

Lion Lesson 1: The Species Question

The Species Question 13 Just for Laughs Let’s Get Practical! So far, all of these definitions of It is really a challenge to come up with species have been for organisms that a definition for a species that works in reproduce sexually—where there are two every case. Because laws to protect parents, male and female. What definition wildlife and biodiversity depend on could be used for organisms that do not defining which organisms are species, all need mates to reproduce? Most of these the conflicting definitions posed a problem species’ offspring are exact copies of for state and federal wildlife agencies. A themselves—clones. For the most part, legal definition of species was needed. wildlife biologists do not need to worry so much about these types of organisms, The Endangered Species Act was since most are bacteria, fungi, plants or revised in 1978 to define the term some other living thing that does not "species" to include “any subspecies of count as “wildlife” under the law. However, fish or wildlife or plants, and any distinct some “female” reptiles, amphibians, and population segment of any species or fish can reproduce without a mate, or vertebrate fish or wildlife which inter- become “male” when need be. breeds when mature.” A subspecies is a population of a species whose members have certain physical and hereditary characteristics distinct from other populations of that species. What is a “distinct population segment (DPS)?” Triploid Checkered For several years after this, there was Whiptail confusion. Since the scientific meanings Many college of species and subspecies can vary, the biology textbooks meaning of “distinct population segment” may list seven or was critically important. Congress was eight definitions of besieged with requests to clarify the “species!” Just for term’s meaning. Congress instructed laughs, type “define species” or “species the Secretaries of the Department of concepts” into an internet search engine the Interior and the Department of such as Google, MSN Search, Yahoo, or Commerce—the federal agencies charged whichever search service you have with implementing the ESA—with available. How many different definitions providing a clear and consistent definition. of species did you find? ______In February of 1996, the Departments List at least three other species concepts adopted a policy to clarify their interpre- that you found: tation of DPS for the purpose of listing, ______delisting, and reclassifying species under ______the ESA. ______

Lesson 1: The Species Question

14 The Species Question The policy used three “tests” to What is your biology textbooks’ definition determine whether the population of of species? distinct population animals was a ______segment: ______1. Discreteness (distinct physical, physio- ______logical, ecological, or behavioral characteristics) of the population segment in ______relation to the remainder of the species to ______which it belongs; ______2. The significance of the population segment (genetic differences, unique Does the textbook definition share any of lineage and area of occurrence) to the the characteristics used to determine a species to which it belongs; and distinct population segment? If so, which ones? 3. The population segment’s conservation status (threatened or endangered) ______in relation to the ESA’s standards for ______listing. ______The characteristics that wildlife biol- ______ogists needed to use to determine ______whether a certain population was a distinct population segment has since been used as a de facto (legal) definition Why is a legal definition of species of species. These characteristics are: necessary? 1. Usually do not interbreed with other ______populations; ______2. Have different appearance, behavior, or ______ecological niche than other populations; ______3. Have notably different DNA (genetic ______material that determines inherited charac- ______teristics); and 4. Represent a unique evolutionary lineage and contain the potential for a unique evolutionary

future. Lesson 1: The Species Question

Pika

The Species Question 15 Lesson 2 Educator’s Overview Birds Of A Feather

Summary Students carefully observe videos of sage grouse filmed at two separate locations in Colorado. They observe photos of the birds and examine data. Based on the physical and behavioral characteristics they observe, students hypothesize whether the birds are the same or different species.

Duration Learning Objectives invisible ink, the bird had been there all along, but researchers One 45-minute After completing this activity, had not had the formula—the class period students will be able to: clues—to make them obvious. • Describe the morphological and The Gunnison sage grouse behavioral differences of two had long been assumed to be the populations of sage grouse Vocabulary same species as the greater sage Avian • Provide evidence that might grouse. Evidence collected for support an argument for over 20 years demonstrated that Biodiversity considering two populations of the two differed starkly in size, Carpal sage grouse as different appearance, behavior, and it Culmen species turns out, DNA. Game • Identify evidence that would be needed to prove that two popu- In this activity, students Lek lation of sage grouse represent review the data that led to this Molt separate species or variations fascinating discovery. Some of a single species students may actually be familiar Morphological with this story, possibly because Tarsus of the location they live in (students in Gunnison perhaps?) or because they have read about Background this in the newspaper. If this is the case, please insist that In the mid-1990s, for the first students look at the evidence time in decades, a wholly new anyway. The story of the grouse species of bird was “found” in presents one of the finest the continental United States. examples of the scientific Like invisible ink suddenly materi- process and “way of knowing.” alizing on blank paper, a new species of bird emerged in the sagebrush ecosystem of western Colorado and eastern Utah. Like

Lesson 2: Birds Of A Feather

16 The Species Question Teaching Strategies organization that the two populations may be separate species, 1. Thoroughly read the student and must specifically state the materials for Birds Of A Feather, nature of their new research and A Closer Look, and Hidden In how that research would resolve Plain View. the question. 2. Give each student the first reading packet, Birds Of A Materials and Feather. Preparation 3. After giving students Extensions sufficient time to read the packet, • Student Reading • Students research Gunnison and Activity Pages present the DVD: Sage Grouse sage grouse and report on any for Birds Of A Observation. Please allow new information about the Feather—one students to view this short video species. photocopy several times. • Recently, another grouse per student 4. After students have recorded species was determined to be • Student Reading their observations from watching two different species. Students and Activity Pages the video, pass the laminated can research this decision to for A Closer Look— photos of the two sage grouse re-classify different populations one photocopy populations around the class and of blue grouse. The interior per student allow time for students to record species (found in Colorado) will • DVD player further observations. retain the same scientific name and monitor 5. Give each student the second (Dendragapus obscurus) but • DVD: Sage Grouse reading packet, A Closer Look, the common name has been Observation changed to Dusky Grouse. The and allow the students to read • Laminated color Pacific species has been split the packet and answer the photographs of questions in small groups. to Sooty Grouse (D. fulig- Sage Grouse in inosus). The decision by the 6. After discussing student Location A American Ornithologists Union (Gunnison County) findings as a class, take a poll to can be viewed at this web site: and Sage Grouse determine how many students http://www.aou.org/checklist/ in Location B think these two populations may (Jackson County) be different species. Record the Suppl47.pdf • Student Reading poll results in a visible place. Also, the scientific paper Pages—Hidden in 7. Give each student the last that confirmed the genetic Plain View, one reading packet, Hidden In Plain differences between the photocopy View. After reading the packet, grouse—Barrowclough, G.F., per student J.G. Groth, L.A. Mertz and ask if any students are surprised • Laminated color R.J. Gutierrez. 2004. with the results. diagram comparing Phylogeographic structure, Gunnison Sage gene flow and species status Grouse and Greater in blue grouse (Dendragapus Sage Grouse obscurus) Molecular Ecology

Assessment 13:1911–1922.—can be found Lesson 2: Birds Of A Feather at: Ask students to write a grant proposal requesting money to http://www.cnr.umn.edu/ continue research on the two fwcb/research/Owls/lit%20 populations of sage grouse. folder/barrowclough%20et% Students must use evidence to 20al.%202004.pdf persuade a government science

The Species Question 17 A brief article can also be found in the 3. Based on this additional data, what 2006 September/October issue of Colorado general statement can you make about sage Outdoors, published by the Colorado Division grouse when you compare males and of Wildlife. females? Female sage grouse are smaller than male sage grouse. 4. What general statement can you make when you compare sage grouse in Gunnison Key to Birds Of A Feather County with sage grouse in Jackson County? The sage grouse in Gunnison County are 1. Observations of Sage Grouse in Location smaller than the sage grouse in Jackson A—Gunnison County County. Answers may vary—these are possibilities: The male sage grouse in Gunnison County 5. What are the legal criteria for defining a have thick feathers on the back and sides species? of their necks—it looks almost like a • Usually do not interbreed with other ponytail. These sage grouse seem to populations; display at slower rates and they pop their • Have different appearance, behavior, air sacs nine times during each display. or ecological niche than other popu- The males throw their neck feathers over lations; their heads and wag their tails at the end of each display. They have distinct white • Have notably different DNA (genetic markings on their tails. material that determines inherited characteristics); and 2. Observation of Sage Grouse in Location B—Jackson County • Represent a unique evolutionary Answers may vary—these are possibilities: lineage and contain the potential for a The male sage grouse in Jackson County unique evolutionary future. have thin feathers on the back and sides of 6. Based on your observations, do these their necks. They pop their air sacs twice populations of sage grouse meet any of the during each display. criteria to be considered different species? Yes, they are different in appearance and behavior. Since they are different sized, it would be logical that they would have Key to A Closer Look different DNA. 7. What other information would you need 1. What general statement can you make before you could determine whether these about sage grouse wings when you compare two populations of sage grouse belonged to males and females? Female sage grouse different species? I would need to know if wings are smaller than male sage grouse these birds would interbreed with each wings. other if given the chance and I would have 2. What general statement can you make to analyze the DNA of both populations to when you compare sage grouse wings determine if it was different. collected in Gunnison County with wings in Jackson County? Sage grouse wings collected in Gunnison County are smaller than sage grouse wings collected in Jackson County.

Lesson 2: Birds Of A Feather

18 The Species Question Notes ______

______Lesson 2: Birds Of A Feather ______

The Species Question 19 Lesson 2 Student Page Birds Of A Feather

That Seventies Show! You are about to view a video of strutting male sage grouse filmed in two It is the 1970’s and biologists are different locations in Colorado. Watch studying sage grouse in Colorado. Since and listen carefully, then record your the 1950’s, sage grouse have historically observations of the birds in both been grouped into two subspecies locations. based on plumage and coloration. The western subspecies is limited to west- 1. Observations of Sage Grouse in central Oregon and Washington, while Location A—Gunnison County the eastern subspecies occupies ______sagebrush habitat to the east of those ______states, including Colorado. ______The sage grouse is one of North ______America’s most spectacular birds. As its ______name suggests, sage grouse live only in ______sagebrush habitat, which provides the birds with food and shelter, and space ______for their traditional courting ritual. Each ______spring, males begin the mating ritual by ______competing for the best position in the ______center of grouse strutting grounds, called leks. 2. Observation of Sage Grouse in Mates of all species of sage grouse Location B—Jackson County are equipped with air sacs on their ______breasts, which they use to attract ______females. The mating call that male sage ______grouse make with their air sacs is audible a mile or more away, and has ______been compared to the sound of bubbles, ______or gulps, underwater. The superiority (as ______determined by other grouse) of the ______male’s call, and the vigor and quality of the rapid head-shaking, strutting dance ______that accompanies it, determine its ______position in the lek. Dominant males ______occupy the center of the lek and win the opportunity to breed with the majority of females.

Lesson 2: Birds Of A Feather

20 The Species Question Student Pages A Closer Look

Photographers travel to Colorado • setting seasons—establishing certain from all parts of the world to capture the times of year people may hunt; stunning sage grouse courtship on film. • issuing licenses that limit the number One well-known wildlife photographer of people who may hunt; and has traveled to the leks in both Gunnison and Jackson Counties and • setting bag limits—allowing only a has taken spectacular pictures. As you certain number of animals to be view his photos, add any observations harvested within a set time limit. you might have to your list. Game populations are closely monitored and hunting regulations are adjusted as needed to conserve these animals for future generations. The sage Winging It grouse harvest was monitored through wings turned in by hunters to DOW biol- In Colorado, sage grouse are ogists. The wings indicate the age and managed as a small game species, one sex of the grouse. that people can legally hunt for food. In order to sustain healthy populations of game animals, wildlife agencies such as the DOW regulate hunting by many means. These can

include: Lesson 2: Birds Of A Feather

Photo courtesy of Bill Haggerty

The Species Question 21 How Do Sage Grouse Wings 14–16 months old. In the fall, when Indicate Age of the Birds? hunting is permitted, P9 and P10 are new and pointed on the juvenile birds, pointed All grouse have ten primary feathers— and worn on yearling birds, and rounded eventually. When the chicks hatch, they on adult birds. have only eight juvenile primaries on each wing. Juvenile primaries 9 and 10 emerge How do researchers tell the sex of the when the chicks are about a month old. sage grouse by the wings? You will soon discover the answer! Grouse molt (drop and replace) their primaries in sequence, starting with P1 and ending with P10. Adults and yearlings replace all ten of their primaries, but juveniles just replace the first eight. They do not molt P9 and P10 until they are

Juvenile Sage Grouse Wing

10* 1 9*

8 2 7 3 6 4 P1 5

P2 *Rounded P3 Adult

P4 Sage Grouse

P5 P6 P7 P8

P10 P9 (pointed) (pointed)

Lesson 2: Birds Of A Feather

22 The Species Question Dr. Clait Braun, an avian (bird) researcher with the DOW, began compiling the wing data for sage grouse populations in the mid-1970’s. He measured three primary feathers (10, 9, and 1) on each wing. Here are the data he has for two different locations—the Gunnison Basin of southwestern Colorado and those from Jackson County in the northwestern part of the state:

ADULT MALES ADULT FEMALES

P10 P9 P1 P10 P9 P1

Gunnison County Mean Length 166 216 151 139 182 130 (mm)

Jackson County Mean Length 179 230 167 147 193 141 (mm)

What general statement can you make What general statement can you make about sage grouse wings when you when you compare sage grouse wings compare males and females? collected in Gunnison County with wings ______in Jackson County? ______

Dr. Braun had the same observations that you did and decided to investigate other morphological (physical) traits of the birds. He decided to compare other physical characteristics of the two populations of birds. Here is his data comparing various features of adult male Lesson 2: Birds Of A Feather and adult female sage grouse in Gunnison and Jackson Counties. All numbers represent the mean measurement for each feature.

The Species Question 23 GUNNISON COUNTY JACKSON COUNTY

Adult Males Adult Females Adult Males Adult Females

Live Body Mass (g) 2,141 1,204 3,190 1,745

Beak Measurements (mm) Culmen* 31.7 28.0 39.1 30.6 Nostril to tip 14.3 12.9 16.6 14.5 Width 16.0 13.8 21.7 17.1

Tarsus Length (mm)* 62.5 58.6 74.4

Carpal Length (mm)* 304 260 340 284

Length of Tail Feathers (mm) <315 347

*Explanation*Explanation ofof bodybody partpart andand measurement:measurement: • Culmen: Straight-line measurement from the base of the upper beak to the tip of the upper beak • Tarsus: Measurement from point where the leg joins the middle toe Culmen to the first joint in the leg • Carpal: With the wing slightly flattened, measurement from the wrist bone of the wing to the tip of the longest primary feather

Juvenile Sage Grouse Wing

Carpal Length Measurement

Tarsus

P10 (pointed) P9 (pointed) P8 P7 P1 P6 P2 P3 P4 P5

Lesson 2: Birds Of A Feather

24 The Species Question Based on this additional data, what 3. ______general statement can you make about ______sage grouse when you compare males ______and females? 4. ______Based on your observations, do these ______populations of sage grouse meet the ______criteria to be considered different species? ______What general statement can you make ______when you compare sage grouse in ______Gunnison County with sage grouse in Jackson County? ______What other information would you need ______before you could determine whether these two populations of sage grouse belonged ______to different species? ______What are the legal criteria for defining a species? ______1. ______2. ______

______Lesson 2: Birds Of A Feather

The Species Question 25 Student Pages Hidden In Plain View

In 1977, Dr. Clait Braun, an avian Fascinated by startling differences in researcher with the DOW, noticed that vocal patterns, she rounded up video and sage grouse wings collected in the audio recorders and went to the leks to Gunnison Basin of southwestern Colorado study the entire mating ritual. Male sage were smaller than sage grouse wings grouse in both the Gunnison and northern collected in northern Colorado. He also areas had a highly elaborate strut display noted that these grouse were one-third that began with males taking a few steps, smaller than the sage grouse found farther and then raising their wings and brushing north, and that the males had more them twice against the stiff feathers of the distinct, whiter tail feathers and more pouch to make swishing noises to elaborate filoplume feathers on their accompany the mating calls. She noted necks. Dr. Braun also documented that sage grouse in Gunnison had fewer differences in leg lengths and beak displays per minute and would also throw shapes. Based on these morphological their filoplumes over their head and wag (physical form and structure) differences, their tail at the end of their display. he began to think that the birds in the Gunnison Basin might be another When Jessica Young tried to play male subspecies. Gunnison County grouse vocalizations in the territories of Jackson County sage Sound from the strutting grounds grouse, the females actively avoided the provided some of the first strong hints that area. She had similar results when she the two groups might in fact be separate tried to romance Gunnison females with species. As an undergraduate student at the sounds of Jackson County sage the University of California at San Diego in grouse males. Young continued to study the 1980’s, Jessica Young had found the Gunnison grouse and to collaborate herself listening to and trying to analyze with Dr. Braun while receiving a Ph.D. at hundreds of tapes of sage grouse as part Purdue and, later, after being named to of a biology project. She noticed different the faculty at Western State College, vocal patterns on tapes of sage grouse which is in Gunnison. from the Gunnison Basin. While sage grouse from northern areas such as Jackson County consistently pop their air sacs twice in each of the many brief strut displays they perform, the Gunnison birds pop their air sacs nine times, and the sounds they produced are notably deeper.

Lesson 2: Birds Of A Feather

26 The Species Question At first, Dr. Braun was hesitant to By the way, the sources of the data come to the extraordinary conclusion that provided for this activity were: the Gunnison grouse was a separate • Hupp, J.W. and C.E. Braun. 1991. species. Nevertheless, in time, he Geographic variation among Sage conceded that Dr. Young simply compiled Grouse in Colorado. Wilson Bulletin 103 too much evidence to conclude otherwise. (2), 255–261. Dr. Young’s research on the behavioral differences of the sage grouse, along with • Young, J.R., C.E. Braun, S.J. Oyler- Dr. Braun’s documentation of morpho- McCance, J.W. Hupp, and T.W. Quinn. logical differences, led to analysis of the 2000. A new species of Sage-Grouse birds’ genetics in 1999. The DNA studies, (Phasianidae: Centrocercus) from by Dr. Tom Quinn and Dr. Sara Oyler- Southwestern Colorado. Wilson Bulletin McCance of Colorado State University, 112 (4), 445–453. provided definitive evidence that the two groups were separate species.

This was the first time in decades that a new species of bird was described in the continental United States. The Gunnison sage grouse did not interbreed with the northern sage grouse; the two are strikingly different in both appearance and behavior; and detailed studies of the two groups’ DNA showed that they were far too distantly related to be considered the same species. Unlike new species discoveries in remote parts of the globe, the Gunnison sage grouse had been in

plain view all along! Lesson 2: Birds Of A Feather

The Species Question 27 Lesson 3 Educator’s Overview Taxonomy Through The Ages Duration Two or three 45-minute Summary class periods Student groups prepare taxonomic groupings that reflect the science of different time periods by rearranging pictures of 24 species of Colorado wildlife. Vocabulary Ancestral character Binomial Learning Objectives on different attributes of the organism. Character After completing this activity, Clade students will be able to: As advances in science have Cladistics allowed us to understand how • Describe different systems of organisms arise and are related, Cladogram classifying organisms. classification became only one Classification • Classify organisms using two aspect of systematics, the much system different systems of classifi- larger field of biology that deals • Five-kingdom cation. with the diversity of life. • Three-domain • Define cladistics and describe Systematics includes both • Two-empire taxonomy its use. , the science of Derived character naming and classifying • Describe the process used to organisms, and phylogenetics, DNA construct a cladogram by the study of the pattern of events Eukaryote comparing ancestral and that has led to the distribution derived characters. Gene and diversity of life. Gene sequencing Cladistics is a method of In-group analysis that attempts to classify organisms by common ancestry. Marine Background It has been around for almost Natural selection There is an amazing diversity fifty years, but has really become Out-group of life. To be able to commu- important in the past few decades, as a means of hypothe- Phylogenetics nicate about various organisms and have a significant way to sizing relationships among Prokaryote study them, humans have always species that can then be tested Selection sought to sort species into mean- with new molecular technologies. ingful groups, or taxa (taxon, High school texts are now Strata singular). Before the advent of beginning to introduce students Systematics modern, genetically based to these important concepts. Taxon (taxa) studies of animals and plants, organisms were classified into This activity takes students Taxonomy different categories based on on a historical journey through Terrestrial their physical characteristics. the classical methods of taxonomy into the new age of Uniformitarianism Often, these groupings were also reflective of the world view at the systematics. This compact pres- time and the importance placed entation of changes in scientific

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

28 The Species Question thought over time can also 6. Allow class time for students facilitate discussions on the to read through parts I and II of processes of science and the the activity and to prepare, relationship of scientific advances present, and defend their classifi- to human history. cation posters to their classmates. 7. Point out to students that Aristotle’s system might include Teaching Strategies some animals in the correct group. He might have grouped 1. Thoroughly read the student bats in the “bird” taxa. He may materials for Taxonomy Through not have recognized bats as The Ages. mammals, or for that matter, 2. Divide the class into groups have had a category for of two to four students. mammals. His system might have 3. Give each student a copy of also grouped an organism like a Materials and duck billed-platypus, another the Colorado Wildlife Cards and Preparation the activity packet, Taxonomy unusual mammal, in the taxa Through The Ages. “Four-legged animals that lay • Student Reading eggs.” The importance of certain and Activity 4. Introduce the idea that attributes of species, such as Packet: Taxonomy scientific ideas and procedures having mammary glands, has Through The Ages may change as new discoveries changed over time. and advances are made. Tell • Copies of students that they will be 8. As a class, read and discuss Colorado Wildlife exploring the developing science Part III: Evolution Theory, Cards—one per student of the classification of organisms, Genetics, And Biotechnology. Be and will later see how classifi- sure that students understand • Scissors the terms that are being used— cation relates to larger species • Glue or tape questions. particularly character, ancestral character, derived character, in- • Poster board, 5. Tell students that they will group and out-group. You may butcher paper or work through parts I and II of the want to have students circle the other presentation activity in their groups. Show in-groups and out-groups on the media them the resource materials alternate forms of the cladogram • Access to (textbooks, library books, and provided. textbooks, library, internet) and the presentation and internet materials that are available to them. To research classification of animals, one of the best Internet sites is University of Assessment Michigan Museum of Zoology Students’ preparation and

Animal Diversity Web: defense of their classification Lesson 3: Taxonomy Through The Ages http://animaldiversity.ummz. posters serve as an assessment umich.edu/site/index.html for this activity. Students can type the scientific or common name into the search box and find the taxonomic groups of each species. This site Extension also provides links to other If the students’ textbooks taxonomy sites. have additional examples of cladograms, review and discuss those as well.

The Species Question 29 Taxonomy Through The Ages Keys • Snakes: Western rattlesnake, Key: Aristotle’s Classification Crotalus viridis Something similar to the following groupings of Blooded Animals should be • Birds: presented: Gunnison sage grouse, Centrocercus minimus • Four-legged Animals that Give Birth: Burrowing owl, Black-footed ferret, Athene cunicularia Mustela nigripes Sandhill crane, Grus canadensis Lynx, Little brown bat, Lynx lynx Myotis lucifugus Mule deer, Odocoileus hemionus • Fishes: American elk, Rainbow trout, Cervus elaphus Oncorhynchus mykiss White-tailed deer, Odocoileus virginianus Bison, Key: Classical Taxonomic Classification of Bison bison Colorado Wildlife Species Pronghorn, Antilocapra americana Colorado Classical Taxonomic Wildlife Classification Black-tailed prairie dog, Species For Each Species The Following Groups Cynomys ludovicianus Are Identical: Red fox, Kingdom: Animalia Vulpes vulpes Phylum: Chordata Subphylum: Vertebrata Moose, Black-footed ferret Class: Mammalia Alces alces Order: Carnivora Mountain lion, Family: Mustelidae Felis concolor Name: Mustela nigripes Bighorn sheep, Lynx Class: Mammalia Ovis canadensis Order: Carnivora Family: Felidae Mountain goat, Name: Lynx lynx Oreamnos americanus Mule deer Class: Mammalia Order: Artiodactyla • Four-legged Animals that Lay Eggs: Family: Cervidae Wood frog, Name: Odocoileus hemionus Rana sylvatica American elk Class: Mammalia Boreal toad, Order: Artiodactyla Bufo boreas Family: Cervidae Tiger salamander, Name: Cervus elaphus Ambystoma tigrinum Western box turtle/Ornate box turtle, White-tailed deer Class: Mammalia Terrapene ornate Order: Artiodactyla Triploid checkered whiptail, Family: Cervidae Cnemidophorus neotesselatus Name: Odocoileus virginianus

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

30 The Species Question Colorado Classical Taxonomic Colorado Classical Taxonomic Wildlife Classification Wildlife Classification Species For Each Species The Following Groups Species For Each Species The Following Groups Are Identical: Are Identical: Kingdom: Animalia Kingdom: Animalia Phylum: Chordata Phylum: Chordata Subphylum: Vertebrata Subphylum: Vertebrata Bison Class: Mammalia Wood frog Class: Amphibia Order: Artiodactyla Order: Anura Family: Bovidae Family: Ranidae Name: Bison bison Name: Rana sylvatica Pronghorn Class: Mammalia Boreal toad Class: Amphibia Order: Artiodactyla Order: Anura Family: Antilocapridae Family: Bufonidae Name: Antilocapra americana Name: Bufo boreas Black-tailed Class: Mammalia Tiger salamander Class: Amphibia prairie dog Order: Rodentia Order: Caudata Family: Sciuridae Family: Ambystomatidae Name: Cynomys ludovicianus Name: Ambystoma tigrinum Red fox Class: Mammalia Western rattlesnake Class: Reptilia Order: Carnivora Order: Squamata Family: Canidae Family: Viperidae Name: Vulpes vulpes Name: Crotalus viridis Moose Class: Mammalia Western box turtle/ Class: Reptilia Order: Artiodactyla Ornate box turtle Order: Testudines Family: Cervidae Family: Emydidae Name: Alces alces Name: Terrapene ornata Mountain lion Class: Mammalia Triploid checkered Class: Reptilia Order: Carnivora whiptail Order: Squamata Family: Felidae Family: Teiidae Name: Felis concolor Name: Cnemidophorus neotesselatus Bighorn sheep Class: Mammalia Gunnison sage Class: Aves Order: Artiodactyla grouse Order: Galliformes Family: Bovidae Family: Phasianidae Name: Ovis canadensis Name: Centrocercus minimus Mountain goat Class: Mammalia Rainbow trout Class: Osteichthyes

Order: Artiodactyla Order: Salmoniformes Lesson 3: Taxonomy Through The Ages Family: Bovidae Family: Salmonidae Name: Oreamnos americanus Name: Oncorhynchus mykiss Burrowing owl Class: Aves Little brown bat Class: Mammalia Order: Strigiformes Order: Chiroptera Family: Strigidae Family: Vespertilionidae Name: Athene cunicularia Name: Myotis lucifugus Sandhill crane Class: Aves Order: Gruiformes Family: Gruidae Name: Grus canadensis

The Species Question 31 Key: Linnean Classification Something similar to the following: Kingdom Animalia

Phylum Chordata

Subphylum Vertebrata

Class Class Class Class Osteichthyes Amphibia Reptilia Aves

Order Order Order Order Order Order Order Order Salmoniforms Anura Caudata Squamata Testudines Galliformes Gruiformes Strigiformes

Family Family Family Family Family Family Family Family Family Family Salmonidae Ranidae Bufonidae Ambystomatidae Veperidae Teiidae Emydidae Phasianidae Gruidae Strigidae

Rainbow trout, Wood frog, Boreal toad, Tiger Western Triploid Western Gunnison Sandhill Burrowing Oncorhynchus Rana sylvatica Bufo salamander, rattlesnake, checkered box turtle/ sage grouse, crane, owl, mykiss boreas Ambystoma Crotalus whiptail, Ornate Centrocercus Grus Athene tigrinum viridis Cnemidophorus box turtle, minimus Canadensis cunicularia neotesselatus Terrapene ornate

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

32 The Species Question Class Mammalia

Order Order Order Order Artiodactyla Chiroptera Rodentia Carnivora

Family Family Family Family Family Family Family Family Cervidae Bovidae Antilocapridae Vespertilionidae Sciuridae Felidae Canidae Mustelidae

Mule deer, Bighorn Pronghorn, Little brown bat, Black-tailed Lynx, Red fox, Black-footed Odocoileus sheep, Antilocapra Myotis lucifugus prairie dog, Lynx lynx Vulpes vulpes ferret, hemionus Ovis americana Cynomys Mustela canadensis ludovicianus Mountain lion, nigripes

American elk, Felis concolor Lesson 3: Taxonomy Through The Ages Cervus elaphus Mountain goat, White-tailed Oreamnos deer, americanus Odocoileus virginianus Bison, Bison bison Moose, Alces alces

The Species Question 33 Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

34 The Species Question Black-footed ferret Mustela nigripes

White-tailed deer Odocoileus virginianus

Lynx Bison Lynx lynx Bison bison

Pronghorn Antilocapra americana

Mule deer Odocoileus hemionus American elk Lesson 3: Taxonomy Through The Ages Cervus elaphus

Black-tailed prairie dog Cynomys ludovicianus

The Species Question 35 Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

36 The Species Question Mountain goat Oreamnos

Red fox americanus Vulpes vulpes Vulpes Burrowing owl Athene cunicularia

Moose Alces alces

Mountain lion Sandhill crane Felis concolor Grus

canadensis Lesson 3: Taxonomy Through The Ages Ovis canadensis Bighorn sheep

Wood frog Rana sylvatica

The Species Question 37 Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

38 The Species Question Bufo boreas Boreal toad

Triploid checkered whiptail Cnemidophorus neotesselatus

Tiger salamander Ambystoma tigrinum Gunnison sage grouse Centrocercus minimus

Western rattlesnake Crotalus viridis Rainbow trout Oncorhynchus mykiss

Western box turtle/Ornate box turtle Little brown bat Lesson 3: Taxonomy Through The Ages Terrapene ornata Myotis lucifugus

The Species Question 39 Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

40 The Species Question Lesson 3 Student Pages Taxonomy Through The Ages

Since ancient times, humans have groupings on his observations of marine been grouping and classifying all types (ocean) and terrestrial (land) life and his of things. Sorting objects or living things dissections of various animals. He into categories may have begun as a divided the animals into two types: those primal means of survival. Labeling or with blood, and those without blood (or identifying other people or tribes as at least without red blood). friends or enemies, plants as edible or poisonous, or animals as safe or The blooded animals were further dangerous could definitely help keep divided into two groups: animals that one alive. gave birth and animals that laid eggs. The animals that gave birth were placed This time-honored human method of into three groups: humans, whales, and bringing order to the world also helps us four-legged animals that gave birth. organize information we have about Animals that laid eggs were grouped organisms and biodiversity. For example, into these categories: birds, serpents if someone discovers a new species and (snakes), four-legged animals that lay groups it with similar animals that have eggs, and fishes. already been studied, he would not need to analyze everything about the new The bloodless animals were clas- organism from scratch. The process sified as cephalopods (such as the of sorting out and classifying life also octopus); crustaceans; insects (which helps biologists answer many species included the spiders, scorpions, and questions. centipedes, in addition to what we now define as insects); shelled animals The science of naming, describing (snails, clams, oysters, starfish, sea and classifying organisms into groups is urchins, etc.); and “zoophytes, called taxonomy. Each named group of or “plant-animals,” which looked like organisms is called a taxon, and the plants (such as coral, sponges, etc). plural of this word—many groups—is taxa. Your Task Using one set of your group’s wildlife species cards; design a poster that

groups the 24 animals according to Lesson 3: Taxonomy Through The Ages Part I: Aristotle Aristotle’s classification system. Aristotle (384–322 B.C.E.), an over- achieving Greek philosopher, was the first to develop a widely used system of Part II: Linnaeus classification for living things. He sorted animals according to their actions or Carl Linnaeus was born in 1707, the way of life, as well as their physical son of a Swedish Lutheran minister. features or parts. Aristotle based his Linnaeus shared his father’s interest in

The Species Question 41 plants and loved nature deeply. His instance, Apis mellifera is the binomial and religious beliefs led him to natural scientific name for the honey bee. theology, a philosophy that taught that it is possible to understand God’s wisdom by The scientific name of an organism studying His creation. The study of nature gives biologists a common way of would reveal the Divine Order of God’s communicating, no matter what their creation, and as a naturalist it was native language. Regardless whether the Linnaeus’ task to construct a “natural researcher is from the United States, classification” that would reveal this order China, Spain or Africa, and no matter their in the universe. alphabet or form of writing, he or she will always use the scientific name in an Linnaeus’s search for a natural system agreed format in any scientific publication. for the classification of living things led The first letter of the genus name is him to group organisms based on shared always capitalized, and the first letter of characters—identifiable features, traits or the second word is always lowercase. The characteristics. He combined his groups scientific name is always either underlined into a hierarchy of subsequently more or in italics. inclusive, higher taxonomic groups. Very similar species were grouped together in a genus; similar genera were grouped into orders, and so on. Linnaeus’ first hierarchy Kingdoms, Empires, And Domains of taxonomic groups included species, Linnaeus’s classification system has genus, order, class, and kingdom. The been used by biologists for over 200 highest taxa, the kingdom, contained years, although it has been slowly groups that shared the most general char- modified as new discoveries were made. acteristics. At first, biologists grouped all of the organisms that they knew into two kingdoms—plants and animals. Even microorganisms were grouped into these What’s In A Name? kingdoms, depending on their color and For centuries species had been given appearance. long, Latin names that described them. For example, the common European During the 1800’s, Ernst Haeckel honey bee was called Apis pubescens proposed putting microorganisms in a thorace subgriseo abdomen fusco pedipus separate kingdom, the protists. This three- posticus glabris utrimque margin ciliates, kingdom system was then expanded to meaning “the bee with a grayish thorax four in the early 1900’s, when scientists and brown belly, and a hind foot that is began to distinguish between bacteria and smooth on the sides and fuzzy on the other microorganisms. The new kingdom margins.” Linnaeus simplified this naming for bacteria was called Monera. system by providing each species with two names or a binomial. The first name The current five-kingdom classifi- of the binomial indicated the genus, or cation system (Monera, Protista, Plantae, group of very similar organisms, that the Fungi, Animalia) found in most high school species belonged to. The second name biology textbooks today was not proposed was unique to the species. The exclusive until 1969. Robert Whittaker proposed that two-part name for a species is now organisms be grouped into kingdoms on referred to as its scientific name. For the basis of three characteristics: cell

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

42 The Species Question structure (prokaryotic cells which have no species—and individual—has a unique nucleus or eukaryotic cells that have a DNA sequence, each species and indi- nucleus), body structure (single-celled or vidual has a unique rRNA sequence. When multicellular) and manner of getting energy he analyzed each organism’s rRNA, Woese or nourishment (photosynthesis, discovered that bacteria fall into two absorption, or ingestion). genetically distinct groups, which he calls Bacteria and Archaea, that are as different Recently, two other methods of clas- from each other as they are from sifying organisms have been suggested. eukaryotic organisms. Woese divides Your textbook may talk about these. The Earth’s organisms into three domains: late Ernst Mayr, a prominent biologist at Bacteria, Archaea, and Eukarya. Harvard, supported a two-empire classification system based on cell structure. Your Task The two empires are called Empire Using your biology textbook and other Prokarya or Prokaryotae (prokaryotes— resources, research the names of the organisms lacking nucleated cells) taxonomic groups of the 24 wildlife and Empire Eukarya or Eukaryotae species. Then, using a second set of your (eukaryotes—organisms having nucleated group’s species cards, design a poster cells). that groups the animals in a Five-Kingdom classification system. Your poster may Another noted biologist, Carl Woese, look a bit like a company’s organizational promotes a three-domain classification chart, because all the animals share char- system. He groups organisms on the acters that group them in the same basis of the genetic makeup of their kingdom, phylum, and subphylum. The ribosomal RNA (rRNA). Just as every chart may look a bit like this:

Kingdom

Phylum

Subphylum

Class Class Class Lesson 3: Taxonomy Through The Ages

Order Order Order Order

FamilyFamily Family

The Species Question 43 You will first need to research the classical taxonomic groups of the 24 species:

Colorado Classical Taxonomic Colorado Classical Taxonomic Wildlife Classification Wildlife Classification Species For Each Species The Following Species For Each Species The Following Groups Are Identical: Groups Are Identical: Kingdom: Animalia Kingdom: Animalia Phylum: Chordata Phylum: Chordata Subphylum: Vertebrata Subphylum: Vertebrata Black-footed ferret Class: Moose Class: Order: Order: Family: Family: Name: Mustela nigripes Name: Alces alces Lynx Class: Mountain lion Class: Order: Order: Family: Family: Name: Lynx lynx Name: Felis concolor Mule deer Class: Bighorn sheep Class: Order: Order: Family: Family: Name: Odocoileus hemionus Name: Ovis canadensis American elk Class: Mountain goat Class: Order: Order: Family: Family: Name: Cervus elaphus Name: Oreamnos americanus White-tailed deer Class: Burrowing owl Class: Order: Order: Family: Family: Name: Odocoileus virginianus Name: Athene cunicularia Bison Class: Sandhill crane Class: Order: Order: Family: Family: Name: Bison bison Name: Grus canadensis Pronghorn Class: Wood frog Class: Order: Order: Family: Family: Name: Antilocapra americana Name: Rana sylvatica Black-tailed Class: Boreal toad Class: prairie dog Order: Order: Family: Family: Name: Cynomys ludovicianus Name: Bufo boreas Red fox Class: Tiger salamander Class: Order: Order: Family: Family: Name: Vulpes vulpes Name: Ambystoma tigrinum

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

44 The Species Question Part III: Evolution Theory, Genetics, And Biotechnology Colorado Classical Taxonomic Wildlife Classification There are periods in human history in Species For Each Species The Following which discoveries and new ideas of all Groups Are Identical: kinds seem to emerge out of nowhere. If Kingdom: Animalia one looks more closely, new ideas Phylum: Chordata usually developed as result of combining Subphylum: Vertebrata old ideas in a unique way. Our newest Western rattlesnake Class: and most useful taxonomic methods— Order: those that utilize DNA and RNA analysis, Family: computers, and all sorts of biotech- Name: Crotalus viridis nology—had their start in the 1800s. Those ideas had their birth thousands of Western box turtle/ Class: years before, with the start of agriculture. Ornate box turtle Order: Family: Name: Terrapene ornata Triploid checkered Class: Building A Better Burger whiptail Order: Since the dawn of agriculture, Family: humans have been trying to alter plants Name: Cnemidophorus neotesselatus and animals to give them traits that were Gunnison sage Class: more desirable—a process known as grouse Order: selection. First, people found ways to Family: domesticate these species. They Name: Centrocercus minimus gathered edible grasses and planted Rainbow trout Class: them near their homes. They penned Order: and herded wild goats, sheep and cattle Family: so that they would not have to spend Name: Oncorhynchus mykiss days looking for something to eat.

Little brown bat Class: These early agriculturists noticed Order: that offspring seemed to have traits Family: that were similar to parents. Although it Name: Myotis lucifugus was a complete mystery as to how it happened, early ranchers found that if they bred the two woolliest sheep, the

offspring would be pretty woolly. If Lesson 3: Taxonomy Through The Ages farmers wanted more grain, they would cross plants with the biggest and most abundant seed heads. Over time, this led to bigger and better food crops, well- fed people, and enough free time in the day to devote to academic pursuits.

The Species Question 45 Figuring Out Fossils organisms, update Linnaeus’s taxonomic hierarchy, and group organisms in In the late 1600s, scientist Robert completely new ways. Hooke—best known for his discovery of the cell—proposed that fossils were the remains of once-living organisms. His hypothesis sounded absurd to most Lyell And Darwin people of his time. In the seventeenth century, nearly everyone thought that Charles Lyell (1797–1875) was the fossils were formed and grew within the leading British geologist of his era. He Earth. They thought there was a shaping studied the strata—layers—of the earth force that could create stones that looked and realized that each differed in the like living things. number, type and proportion of marine shells (fossils). Each layer represented a Hooke was the first person to examine different era of Earth’s history. He found fossils with a microscope. He noted close evidence for the then-controversial similarities between the structures of hypothesis of uniformitarianism, the idea petrified wood and fossil shells on the one that the earth was shaped entirely by hand, and living wood and living mollusk slow-moving forces acting over a very shells on the other. Hooke believed that long period of time. He assumed that the the features he could see in fossils were kinds of activities which affected the earth similar to those found in living organisms. in the past must have been exactly like He concluded that dead plants and those in operation in the present (such as animals could be turned to stone by being erosion, sediment deposition, volcanic submerged in water rich in dissolved action, earthquakes, etc.). minerals. Over time, the minerals which were deposited throughout the body of Lyell’s ideas influenced a close the organism would replace each cell. personal friend of his, Charles Darwin. Comparing living organisms to fossils, As Hooke continued to study fossils Darwin (1809–1882) hypothesized that and compare them with living organisms, populations of organisms could change he concluded that many fossils repre- over time. Just as farmers and ranchers sented organisms that no longer existed could slowly improve their crops and on Earth and that fossils could be used to livestock over time, he proposed that wild understand the history of life. organisms could slowly change by a process he called natural selection. “There have been many other Species Natural selection is often referred to as of Creatures in former Ages, of which survival of the fittest. Life is a constant we can find none at present; and that struggle for survival, thought Darwin, and ’tis not unlikely also but that there may more individuals are produced in a popu- be divers new kinds now, which have lation than will be able to survive and not been from the beginning.” reproduce. Those individuals who possess characteristics that allow them to adapt to This was an incredibly radical thought their environment are more likely to survive at the time. A century later, two other and pass on these adaptive traits to their scientists developed theories that would offspring. Over time, an increasing not only support Hooke’s ideas, but proportion of a population will possess the change our understanding of living adaptive traits.

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

46 The Species Question The Gene Connection The New Taxonomy Later research showed how physical According to this idea, organisms that traits could be passed on to future gener- are more similar to one another than they ations. In 1865, Gregor Mendel’s experi- are to other organisms have descended mented on peas and demonstrated that from a more recent common ancestor. traits could be passed to offspring propor- Taxonomists are now actively constructing tionally in discrete units—later named a new “natural system” for the classifi- genes. In 1902, a British physician named cation of organisms based upon the Archibald Garrod observed that the evolutionary relationships of taxa. disease alkaptonuria is passed from one Systematics, a large field of biology that generation to the next in the same deals with the diversity of life, combines proportion as the features of Mendel’s taxonomy and phylogenetics, the study peas. Garrod had discovered the first of the pattern of events that led to the disease recognized to have a genetic diversity of life. cause! The method of analysis that most biol- Meanwhile, in 1882, Walter Flemming ogists use to reconstruct evolutionary rela- was able to stain chromosomes and tionships of organisms is called cladistics. observe the process of cell division. In Cladistics can be used to hypothesize the 1911, while studying fruit flies, Thomas order in which different groups of Hunt Morgan found that chromosomes organisms evolved. Organisms that share carry genes. By 1952, Alfred Hershey and important characters are placed together Martha Chase discovered that genes are into taxonomic groups called clades, that made of DNA and the following year, branch from a single “twig.” With respect Francis Crick and James Watson to two different groups or clades, a described the double helix structure of character is defined as an ancestral DNA. The genetic code was cracked in character if it evolved in a common 1968, when Marshall Nirenberg and others ancestor of both groups. For example, all figured out that the order of the four of the 24 animals that you have been clas- nitrogen bases in DNA (A, G, T, and C) sifying have a backbone or vertebra. A determines the amino acid sequence of backbone is an ancestral character. A trait proteins. that evolves in one group and not another is called a derived character. All the The combined research clearly demon- birds, mammals, reptiles and amphibians strated that DNA coded for all the charac- have four limbs and fish do not. Having teristics possessed by an organism. four limbs is a derived character that Anytime the order of the nitrogen bases evolved later. However, when comparing found in a strand of DNA changed, the birds with the other four-limbed

changes were passed on to offspring. The organisms, four limbs becomes the Lesson 3: Taxonomy Through The Ages changes in traits that the DNA coded for ancestral trait. Having forelimbs (front would be inherited by future generations! limbs) developed into feathered wings It seemed likely that the more traits becomes the new derived character. species had in common, the more similar their genetic code and the more After looking at the various characters “related” they were. that different groups share, scientists create cladograms, branching diagrams that represent a hypothesis about the order in which organisms evolved.

The Species Question 47 Cladograms convey comparative infor- Construction A Cladogram mation about relationships. Organisms The first step in constructing a that are grouped more closely on a cladogram involves analyzing characters in cladogram share a more recent common a data table. The table below will be used ancestor than those farther apart. Because to record whether characters are present the analysis is comparative, cladistic or absent in several vertebrate species analysis deliberately includes an organism you have been studying. A non-vertebrate, that is only distantly related to the other or animal that doesn’t have a backbone, organisms. This distantly related organism will represent the out-group for our is called an out-group. The out-group comparison. Notice that the all the traits in serves as a base line for comparison with the column for the out-group are marked the other organisms being evaluated, the with a 0, which means that the animal in-group. does not have the character. If the organism has the new derived character, the column is marked with a 1.

Vertebrate Cladistic Analysis

CHARACTER Starfish (Out-group) Rainbow Trout Tiger Salamander Ornate Box Turtle (Character Present = 1) (Character Absent = 0) Burrowing Owl

Vertebrae or backbone 01111 Four limbs 00111 Embryo surrounded by water and enclosed within specialized 00011 membranes (amniotic egg) Forelimbs function as wings 00001

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

48 The Species Question The second step is to draw a diagonal line. The bottom of the line represents the remote past. The top of the line is represents a more recent time. Each branch that is drawn from the diagonal line will represent a clade (group of organisms). Now, starting with a diagonal line to represent evolutionary time, the out-group (starfish) is placed on the lowest, “oldest” branch. All the in-group organisms will be found on the upper or more recent branches. Starfish Rainbow Trout Tiger Salamander Ornate Box Turtle Burrowing Owl

Wings

Amniotic egg

Four limbs

Vertebrae

Between each branch that is drawn on the cladogram, a derived feature is listed. Just past the first branch, the most common derived character—having a

backbone—is listed. Between the second and third branch, the next most common Lesson 3: Taxonomy Through The Ages derived character—four limbs is listed, and so on. The clade that has the least common derived character, which is thought to be the character that most recently occurred, occupies the upper branch.

The Species Question 49 Please—Don’t Let This Confuse You! Cladistic analysis is a bit of a new thing and scientists haven’t agreed on a format of presentation. So, sometimes a cladogram that represents the very same thing as the one we just showed you will 4 look like this: Burrowing Owl 3

Ornate Box Turtle 2 Tiger Salamander 1

Rainbow Trout

Starfish

Or this: Starfish

Rainbow Trout

1 Tiger Salamander

2 Ornate Box Turtle 3 Burrowing Owl

Lesson 3: Taxonomy Through The Ages Lesson 3: Taxonomy

50 The Species Question Or this: Ornate Box Turtle Burrowing Owl

4 Tiger Salamander Tiger

3 Rainbow Trout

1 1 Vertebrae

2 Four limbs Starfish 3 Amniotic egg

4 Wings

The reason we are showing you this now is because you will see all of these formats in magazines or newspapers and Lesson 3: Taxonomy Through The Ages also in books, and some of the activities you will be doing. Think of this as a stretching exercise for your brain. It’s important to have a flexible body and mind!

The Species Question 51 Lesson 4 Educator’s Overview

Duration Understanding Ungulate Phylogeny One 45-minute class period Summary Vocabulary Students use cladistics to determine the evolutionary Ancestral characters* history of nine groups of ungulates. Artiodactyls Brachydont Bunodont Learning Objectives pattern of events that led to the Canines distribution and diversity of life, Cannon bone After completing this activity, both living and extinct. It was Carpals students will be able to: founded by Willi Hennig, a Character* German entomologist in 1950, • Define cladistics and describe Clades* and in the past few decades has its use Cladist* become the most commonly Cladistics* • Read a cladogram and used method to examine evolu- Cladogram* describe the information that it tionary relationships of Derived characters* illustrates organisms. Diastema • Sort through various characters Digitigrade of limb structure, tooth Cladists, biologists who use Digits structure and dentition, form of cladistics, use the appearance Herbivorous stomach and type of horn and of what they believe to be Homologous decide which characters are derived or newly evolved traits structures* ancestral and which are derived to assemble organisms into Hypsodont groupings—taxa—that appear to • Construct a cladogram that Incisors represent the evolutionary history demonstrates the phylogeny of of the species. All members of In-group* nine groups of ungulates Mesaxonic each natural group are thought to be monophyletic, to have char- Metacarpals • Describe how cladistics is used acteristics in common because Metatarsals to classify organisms into they evolved from a common Metapodials groups ancestor. These monophyletic Molars taxa are called clades. After Monophyletic group* looking at the various characters Out-group* that different clades share, Paraxonic Background cladists create cladograms, Perissodactyls branching diagrams that Phylogeny* Systematics, a large field represent a hypothesis about Plantigrade of biology that deals with the the order in which organisms Premolars diversity of life, combines evolved. They can then test their Ruminants taxonomy and phylogenetics, hypotheses about species rela- Selenodont the study of the pattern of events tionships through DNA and rRNA Stance that have led to the distribution sequencing, computer modeling Tarsals and diversity of life. Cladistics is and other techniques. Ungulate* a system of analysis used by Unguligrade biologists to reconstruct the

Lesson 4: Understanding Ungulate Phylogeny

52 The Species Question Cladistic hypotheses about derived traits appear, all of the the relationships of organisms organisms “downstream” from can also be used to predict traits this change also receive this new or characteristics of the character from their ancestors. organisms. For example, if biol- 5. After reviewing the vertebrate ogists are searching for particular cladogram, students use these genes or biological compounds same procedures to generate a to improve crop yield or produce character table and cladogram medicines, cladistics can help for ungulates, hoofed mammals. narrow the range of organisms that need to be examined. 6. Students must first look at Cladistics can also be used to the Table of Ungulate Characters determine the genetic differences and answer some analysis between different populations for questions. These questions will species conservation plans or help students look at different help predict resistance or vulner- characters in a way that will help ability to disease in certain them do their cladistic analysis. Materials and organisms. 7. The table Ungulate Cladistic Preparation Analysis is started for students • Student Reading and includes the one character and Activity Pages that defines Artiodactyls, a type from Lesson 3, Teaching Strategies of ungulate. The character is Taxonomy through paraxonic symmetry—having the Ages—retained 1. Thoroughly read the student the symmetry of the foot pass by each student materials for Understanding between the third and fourth Ungulate Phylogeny. • Student Reading digit. Notice that when characters and Activity Pages 2. Copy and post a list of the are assigned to the out-group Understanding starred (*) vocabulary words in a (rhinos), the out-group possesses Ungulate highly visible place. These are the none of the characters of Phylogeny—one only words that students should Artiodactyls. Having a group that per student possesses all (0) scores provides be held accountable for defining. • Important a place to “root” the phylogenetic vocabulary words, 3. Divide the class into groups tree or cladogram. Encourage of two to four students. those with an *, students to assign characters to posted in a 4. You may wish to have the table in a dichotomous visible place students read and complete fashion. That is, each character Understanding Ungulate listed should include all of the Phylogeny on their own. remaining species with (1) scores However, it is recommended that except one. you review what cladograms 8. After students complete this Lesson 4: Understanding Ungulate Phylogeny portray and how they are assignment, you may wish to constructed with your students. have students share and defend This review takes another look at their cladograms. Some students the cladogram from Lesson 3, may complain that there are not Taxonomy through the Ages. First enough characters listed in the review the data table table to completely—or easily— construction with students. sort the species. You can Emphasize that organisms that recommend further research possess a trait receive a (1) in the or discuss the difficulty in table. If they lack that trait they constructing cladograms. Remind receive a (0). Make sure that students that cladograms students notice that as new represent testable hypotheses of

The Species Question 53 evolutionary relationships. Cladograms are relatedness of species. The artiodactyls in just ideas that scientists have that they can the same clade should be the most similar test with other types of technology. and might have a greater potential to transmit disease between species. Biologists would need to extract prion protein from the species thought most closely related and do DNA or RNA Assessment sequencing to check to see if the prions were indeed similar. Students’ preparation and defense of their cladograms represent an assessment for this activity. Key: Analysis Questions 1. How does the number of toes differ Extension between the rhinoceros and other ungulate groups in the table? Rhinos have three (an Pose the following situation to students: A odd number of) toes while the other protein called a prion is thought to be ungulates have two or four toes. Also, responsible for the group of diseases called rhinos are mesaxonic and all others are transmissible spongiform encephalopathies paraxonic. Therefore, rhinos are perisso- (TSEs). The prion protein is a normal protein dactyls and all others are artiodactyls. that has been found in most eukaryotic cells from yeast to humans. An abnormally shaped 2. Which character is ancestral in the prion protein is associated with these deadly “Stomach” column, and which seems to be neurological diseases. Evidence indicates that most recently derived? A simple, 1- abnormally shaped prion proteins can chambered “gut” is ancestral (it’s a influence normal prion molecules to assume character of the out-group, the rhino), the same abnormal shape. Evidence also while the complex 4-chambered, rumi- shows that the abnormal prions that cause nating “gut” is the most recently derived. TSEs have appeared to be of different 3. Which families could be regarded as “true “strains” that can affect the prions of some ruminants”? According to the table, “true species, but not others. The relatedness of ruminants” with complex 4-chambered, certain species may influence the frequency of ruminating “gut” would include transmission of prion diseases from one Antilocapridae (pronghorn), Giraffidae species to another. (giraffe), Bovidae (sheep, musk ox, cattle, goat, bison), and Cervidae (deer, elk, The artiodactyl family Bovidae currently reindeer). contains gazelles, sheep, musk oxen, goats, cattle and bison. Scrapie, the prion disease in 4. Place the families in order according to sheep, has been recognized since the 18th increasing complexity of the stomach. Rhino century. It is believed that the prion disease in (Rhinocerotidae), pigs (Suidae), hippo cattle, bovine spongiform encephalopathy (Hippopotamidae), camel (Camelidae), (BSE), may have appeared after cattle were mouse deer (Tragulidae), pronghorn fed meat and bone meal containing sheep (Antilocarpidae), giraffe (Giraffidae), cattle meat with scrapie in the 1950s. How could a (Bovidae), deer (Cervidae) in any order. biologist use a cladogram to help design a 5. What other structures do those families testable hypothesis regarding transmission of with the most complex stomachs share? They scrapie to cattle and other ungulate species? share the characters: paraxonic, cannon What types of technology would be necessary bone, unguligrade, no upper incisors, long to test this type of hypothesis? Cladograms diastema, and bony horns or antlers. are used to hypothesize the evolutionary

Lesson 4: Understanding Ungulate Phylogeny

54 The Species Question 6. Below is a table “Ungulate Cladistic 8. Would a cladogram based upon DNA Analysis.” The characters that you choose for sequence data be similar to the one that you your table should separate one family or just constructed? Probably. Explain why or group from those that remain. To get you why not. DNA carries the code for proteins started, the first character has been placed in that make structures, so any changes in the table for you. If quite a few characteristics DNA could also change structures coded separate the remaining members choose only by DNA. one of those on your table. Choose the character that you believe provides the greatest advantage for survival. Tables will vary depending on the characters chosen. The data that fill the table should have a pattern similar to Character Table 1 with lines exchanged according to the species list. Any table that a student can defensibly demonstrate dichotomous characters separating clades is acceptable. Here’s an example of a beginning of a possible table:

Ungulate Cladistic Analysis

CHARACTERS Rhino (Out-group) Suidae Hippopotamidae Camilidae Tragulidea Giraffidae Bovidae Antilcapridae Cervidae

Paraxonic 0 1 1 1 1 1 1 1 1 3 or 4 Chambered Gut 0 0 1 1 1 1 1 1 1 Ruminating Gut 0 0 0 1 1 1 1 1 1 Completely Fused Cannon Bone 0 0 0 0 1 1 1 1 1 Bony Horns or Antlers 0 0 0 0 0 1 1 1 1 Hypsodont Cheek Teeth 0 0 0 0 0 0 1 1 1 Horn Sheath or Antlers Shed Annually 0 0 0 0 0 0 0 1 1 Antlers 0 0 0 0 0 0 0 0 1

7. Use the data from the character table to construct a cladogram of Artiodactyl Lesson 4: Understanding Ungulate Phylogeny ungulates.

Rhino Suidae Hippopotamidae Camilidae Tragulidea Giraffidae Bovidae Antilcapridae Cervidae Depending upon the characters chosen in their analysis table, student cladograms will vary. Here’s a possible cladogram that represents the characters chosen in the hypothetical analysis table above.

The Species Question 55 Lesson 4 Student Pages Understanding Ungulate Phylogeny

Wow! The title of this lesson may seem which came first, the camel or the pig? Or a bit intimidating. Resist the urge to raise was it the giraffe or the cow? Or possibly, your hand and ask for a pass to the could it have been the elk or the restroom, the nurse, or whatever. This hippopotamus? really isn’t going to be too difficult. Keep in mind that scientists have a language of In order to answer these questions, their own. They are not trying to confuse you need to use cladistics. Your razor- anyone. Just the opposite, scientists use sharp memory may recollect from the last all these crazy sounding big words to lesson that cladistics is a method of communicate accurately. Usually, many analysis that biologists use to reconstruct scientific terms are built from words of the evolutionary history of organisms. That “dead” languages—like Latin. Since no is, biologists use cladistics to reconstruct one speaks Latin anymore, the meaning of the pattern of events that have led to the Latin words does not change. If scientists diversity of life, both living and extinct. You just used plain ol’ American, there’s a will need to sort through all the various chance they could be misunderstood. In characters (physical features) of these “living” languages, the meaning of words hoofed animals and determine which can change over time. For example, think features are older (ancestral) and which of how your grandparents might have are more recent (derived). defined the words “tight,” “hit,” or “cool” when they were your age. How many different meanings can you think of for these three simple words? Then, there are Another Big Word And A Quick those brand new words, like “blog” or “podcast.” You can see why these funky Review scientific terms are necessary. A basic assumption of cladistics is that the greater the number of shared derived characters between two species or groups, the more recent their common Which Came First? ancestor and the more closely they are related. In other words, the more similar To speed things up, all the tough two organisms are, the more closely words in this lesson are going to be related they are. Organs and body parts translated for you. Let’s start with the title. that are alike in structure and origin are If you recall Lesson 3—and you probably said to be homologous structures. For remember that lesson as clearly as you example, the front legs of an elephant, the remember what you had for breakfast this wings of a bird, the flippers on a sea lion, morning—the word phylogeny means an and the arms of a human are all organism’s evolutionary history. An homologous to each other. Each ungulate is a hoofed mammal. So, in this represents a version of forelimbs. When lesson, you will be trying to figure out

Lesson 4: Understanding Ungulate Phylogeny

56 The Species Question different organisms share a large number Not All Features Are Created of homologous structures, it is considered strong evidence that they are related to Equal each other. These related organisms are thought to have had a common ancestor When you compare all of the char- at some time in the past. acters that each ungulate has, keep in mind that not all features are equally Let’s re-examine the cladogram of the important in determining evolutionary rela- vertebrates found in Lesson 3 to be sure tionships. If every single animal shares a you understand how cladograms are feature, it may not be all that useful for made. A cladogram is a diagram that tracing ancestry. For example, a two- represents a hypothesis of the sequence opening gut (with a mouth at one end and in which new species evolved. Ancestral an anus at the other) is an ancestral traits are found among more groups of character. Nearly all animals have a two- organisms. Fewer groups of organisms opening gut—from cockroaches to fish to share derived traits that appeared more humans. This feature cannot tell us much recently. about the relatedness of these species.

Notice the first branching point of the The features that are most helpful in cladogram. The organism that represents figuring out a species’ ancestry are newer the first branch is one that doesn’t share modifications of older traits—derived the common ancestral characteristic—it characters. For example, many animals is the out-group. The starfish does not have digits (fingers or toes) on their have a backbone, the commonly shared forelimbs, but only humans, apes and ancestral trait. Each group of organisms monkeys have opposable thumbs. No that represent the branches that follow other animals have this feature. Cladists has a backbone—they are part of the (biologists who practice cladistics) try to in-group. identify branching points where characteristics like this first appear to determine Now this next statement is really species’ family trees or lines of descent. important so this author is going to put it Then they group the species—humans, in BOLD ITALICS so that you will know apes, and monkeys—which share the just how important it is. derived character of opposable thumbs into a clade—a group believed related by As further new characters appear, each common origin. Clades are monophyletic descendant group or clade possesses groups, meaning they have one (mono) the new derived character AND all of the common ancestor.

ancestral characters of its ancestors. Lesson 4: Understanding Ungulate Phylogeny In other words, the tiger salamander has the new derived character—four limbs— and a backbone. The ornate box turtle has Lots Of Big Words And One the new derived character—an amniotic egg—and four limbs and a backbone. You Guarantee get the picture. First, the bad news—there’s a ton of big scientific words in this next part. The good news is that these words are not ones you need to memorize. Your teacher has signed a statement guaranteeing that

The Species Question 57 you will not be tested on the meanings the large amounts of cellulose found in of these words. The scientific names of plants, some ungulates have modified all the ungulate characters are just guts with multiple chambers which allow explained so that you can fill out a table them to get the most nutrition from their and draw a cladogram. Of course, if you food. The first chamber acts as a fermen- want to impress your friends and relatives tation vat where microorganisms break by actually learning these words, go right down the plant fibers and cellulose. ahead. This partially digested food is regurgitated back into the mouth, chewed again, re-swallowed into the second chamber of the gut, and then passed to the third and Starting At The Top fourth gut sections which further digest the food. Ungulates that possess these Mammals require a greater amount of complex “stomachs” are called food than most other animals to support a ruminants. higher body temperature and provide energy for the development and growth of Teeth also are important in digestion. young. Adaptations that increase effi- Although all vertebrates except turtles and ciency in finding, eating, and digesting birds have teeth, the teeth of mammals food are important for survival. Ungulates are the most specialized. Tooth structure are no exception. Most have specialized is important for studying mammalian stomachs and teeth, adaptations that phylogeny and the process and pattern of allow them to extract the most energy evolution. Premolars and molars are from their food source. cheek teeth and come in various sizes and shapes to help ruminants grind their food. Ungulates are herbivorous—plant Premolars are usually simpler and smaller eaters. While most animals lack the than the molars at the rear of the mouth. digestive enzymes needed to break down Brachydont molars are low-crowned, while hypsodont molars are high crowned. Selenodont molars have hard enamel ridges running from back to front. This type of molar is common in grazers because these hard ridges increase the number and size of cutting surfaces in the mouth. Animals Canines with a more varied diet usually have bunodont teeth that Diastema are squarish with CHEEK TEETH (Molars and Premolars) Incisors low rounded cusps, like human molars.

Lesson 4: Understanding Ungulate Phylogeny

58 The Species Question Incisors are typically found at the front Like us humans, the earliest mammals of the mouth and are used for grasping, had five digits on each limb. Digits are picking up, or biting off food. The incisors numbered 1 (thumb, big toe) to 5 (“little” may be followed by a toothless gap called finger). The bones in our fingers (carpals) a diastema. Canines are most often used and toes (tarsals) are attached to the for stabbing and holding prey. Males bones in our hand (metacarpals) and foot typically have larger canines than females (metatarsals). Metacarpals and in species that use their canine teeth as metatarsals are also called metapodials. weapons for social displays or fighting. In ungulates, the 3rd and 4th metapodials Herbivorous species that do not capture may be fused to form a single, stronger prey may have smaller canines or lack cannon bone. Walking on tiptoes, them altogether. lengthening metapodials or reducing their numbers, and reducing the number of digits are adaptations for increasing stride length and speed while reducing effort and increasing endurance in locomotion.

Selenodent Teeth

Moving To The Bottom Another important feature is the ability to escape from being eaten by some other animal. In other words, it helps to be able to run really fast. Stance, how an animal stands, can determine how quickly an animal can move while walking or running. Some species like humans place the full length of the foot on the ground during their stride (plantigrade), some walk on the length of their digits

like dogs (digitigrade), Plantigrade Lesson 4: Understanding Ungulate Phylogeny Cannon and others walk on Bone their tiptoes like deer (unguligrade). An unguligrade stance helps Digitigrafe to increase stride length and speed. Hoofs METAPODIALS hardened with the protein keratin help ungulates walk with their full weight Unguligrade on their toes.

The Species Question 59 The number of digits or toes divides Analysis Questions ungulates into two orders, Perissodactyla and Artiodactyla. Perissodactyls are odd- 1. How does the number of toes differ toed ungulates having either one or three between the rhinoceros and other weight bearing toes. Perissodactyls are ungulate groups in the table? mesaxonic, the line of symmetry passes ______through their center toe—which is enlarged and bears most of the weight. ______Artiodactyls are even-toed ungulates with ______two or four toes. Artiodactyl have lost the ______first digit on each limb making them ______paraxonic—the line of symmetry passes ______between the two centermost toes and bears the body’s weight. ______

The Ungulate Cladogram 2. Which character is ancestral in the “Stomach” column, and which seems to Use the information in the Table of be most recently derived? Ungulate Structures to answer the following questions. The answers to the ______questions may help you decide which ______characters are ancestral and derived. Just ______like a real cladist, you will need to ______determine which characters are shared among the greatest number of groups. ______Then, construct a cladogram for the eight ______families of ungulates. The rhinoceros ______(Family Rhinocerotidae) will be the out- ______group. Rhinos have three toes on each foot and are considered perissodactyls. ______Scientists believe that rhinos shared a common ancestor with ancestral artio- ______dactyls some 83 million years ago. ______

Lesson 4: Understanding Ungulate Phylogeny

60 The Species Question 4. Place the families in order according to increasing complexity of the stomach. ______

5. What other structures do those families with the most complex stomachs share? ______6. Below is a table “Ungulate Cladistic ______Analysis.” The characters that you choose ______for your table should separate one family or group from those that remain. To get ______you started, the first character has been ______placed in the table for you. If quite a few ______characteristics separate the remaining ______members choose only one of those on your table. Choose the character that you ______believe provides the greatest advantage ______for survival.

Ungulate Cladistic Analysis

CHARACTERS

Rhino (Out-group) Lesson 4: Understanding Ungulate Phylogeny Paraxonic 0

The Species Question 61 7. Use the data from the character table to construct a cladogram of Artiodactyl ungulates.

8. Would a cladogram based upon DNA sequence data be similar to the one that you just constructed? ______Explain why or why not. ______

Lesson 4: Understanding Ungulate Phylogeny

62 The Species Question Cervidae deer, elk) (deer, rein- Suidae (pigs, hogs) Bovidae ruminating nonruminating ruminating 4-chambered; 2-chambered; 4-chambered; 4-chambered; 2-chambered; 4-chambered; cattle, bison) musk ox, goat, (gazelle, sheep, Tragulidae chevrotain) ruminating; a 3-chambered (mouse deer, 4th chamber is 4th chamber poorly developed okapis) (giraffe, Giraffidae antelope) (pronghorn Antilocapridae TABLE OF UNGULATE CHARACTERS OF UNGULATE TABLE (hippopotamus) Hippopotamidae

llamas) Lesson 4: Understanding Ungulate Phylogeny (camels, y-shaped Camelidae Partially fused 34 4 224 4 44 NoNo Yes Yes Yes Yes No No No No No Yes No No Yes Yes No No No Yes, No Yes Yes Yes Yes No Yes YesYes Yes Yes Yes No Yes Yes Yes Yes Yes Yes Yes Yes Yes No Yes Yes Short Long Short Long Long Long Long Short Long Mostly Selenodont & Brachydont Hypsodont & & Brachydont Selenodont Hypsodont & & Brachydont Hypsodont & Simple 3-chambered; 3-chambered; 4-chambered; 4-chambered; 4-chambered; 4-chambered; 3-chambered; Simple 3-chambered; Mesaxonic Paraxonic Paraxonic Paraxonic Paraxonic Paraxonic Paraxonic Paraxonic Paraxonic Digitigrade Digitigrade Digitigrade Unguligrade Unguligrade Unguligrade Unguligrade Unguligrade Unguligrade Brachydont Bunodont Selenodont Selenodont Selenodont Bunodont Selenodont human hair annually boney core, core, not shed [Out-group] (rhinoceros) 1-chambered; ruminating1-chambered; nonruminating ruminating ruminating no boney core (same stuff as sheath is shed sheath with sheath with boney annually nonruminating Horns of keratin Horns of keratin No No horn Keratin horn Keratin No horn Keratin No Antlers, shed and fingernails), not shed Rhinocerotidae Gut Stride Length Family Family Antlers? Diastema Symmetry Fused into Horns with 3rd and 4th (members) Cheek Teeth Metopodials Bony Core or Cannon Bone? Upper Incisors Upper Canines Lower Incisors Lower Canines Foot Structure/ Number of Toes

The Species Question 63 Lesson 5 Educator’s Overview The Pocket Gopher Cladogram Conundrum

Summary Using the principle of parsimony, students use morphological characteristics and differences in DNA sequences to determine the most likely cladogram to represent the Duration phylogenetic (evolutionary) relationship of four closely related species of pocket gopher. One or two 45-minute class periods Learning Objectives Background After completing this activity, Cladistic analysis is based on Vocabulary students will be able to: the assumption that life arose on Earth only once. All the diversity Analogous character • State the principle of parsimony of life that now exists on Earth is and describe how it is applied Ancestral character thought to have been produced in cladistic analysis. through the reproduction of Character state • Choose six characters that may existing organisms. In other Convergent evolution be important to the survival of words, just as your students had Derived character pocket gophers and use these to have been born from parents, characters to construct a and they have had to have had Evolutionary character table for four species parents (grandparents), all systematics of pocket gopher. organisms have ancestors. If the Homologous evolutionary history, or • Evaluate three hypothetical character phylogeny, of an organism is cladograms based on morpho- traced back, it connects through Parsimony logical characters and select shared ancestors to lineages of Phylogenetic tree the one that most likely other organisms. Phylogeny represents the phylogeny of four species of pocket gophers That all life is connected in using the principal of an immense phylogenetic tree parsimony. is one of the most significant • Distinguish between a clado- discoveries of the past 150 years. gram and a phylogenetic tree. Often, evolutionary relationships • Evaluate three hypothetical between species are difficult to cladograms based on DNA figure out. This lesson discusses sequences and select the one how the principle of parsimony— that most likely represents the that any hypothesis that requires phylogeny of four species of fewer assumptions is a more pocket gophers using the defensible hypothesis—is used to principal of parsimony. determine which cladogram

Lesson 5: The Pocket Gopher Cladogram Conundrum

64 The Species Question hypothesis most likely represents class to ask questions and the phylogeny of any group of comment on the choices. organisms.

Teaching Strategies Assessment Student ability to evaluate 1. Thoroughly read the student three hypothetical cladograms materials for The Pocket Gopher based on physical characters Cladogram Conundrum. and DNA sequences, select the 2. Divide the class into groups one that most likely represents of two to four students. the phylogeny of four species 3. Give each student a copy of of pocket gophers, and defend the The Pocket Gopher their selection using the principle Cladogram Conundrum, Pocket of parsimony serves as an Materials and assessment for this activity. Gophers of Colorado, and Preparation Characters of Colorado Pocket Gophers. • Student Reading and Activity Pages 4. Introduce the idea of for The Pocket parsimony—that the hypothesis Extension Gopher Cladogram with the least assumptions is Student groups can exchange Conundrum— usually the easiest to defend. You papers and try to follow the logic one photocopy can tell students this is the of other groups. They can per student “KISS” rule (Keep It Simple, Silly) comment on the selection of • Student Page of science. characters. Students can then Pocket Gophers 5. You may wish to work compare the class results and of Colorado— one photocopy through the example of discuss whether any particular per student parsimony given in the student cladogram was most useful in pages as a class. You may need representing the evolutionary • Student Page to review the form of the relationships of pocket gophers. Characters of cladogram—that each branch Colorado Pocket represents a different lineage. Gophers— one photocopy 6. When you are convinced that per student students understand parsimony Key

and how to apply the principal to Lesson 5: The Pocket Gopher Cladogram Conundrum 1. Look at the table Characters evaluate conflicting cladograms, of Colorado Pocket Gophers have students work in small again. Looking at the characters groups to complete the activity. that have been provided and the 7. After student groups have characters you observed, choose completed the activity, ask six characters that you believe groups to present their data table might have the most impact on and show how they used the the day to day survival and repro- principal of parsimony to decide duction of the four species of which of the three hypothetical pocket gopher. Explain why you cladograms best represent believe the six characters that pocket gopher phylogeny based you selected would help a pocket on the characters that they gopher adapt to its environment. selected. Allow the rest of the Answers will vary.

The Species Question 65 2. Place the six characters in the table below 5. What other types of characters, besides and indicate the “state” for the character for external appearance, could be used to each species. Answers will vary. construct a data table and a cladogram? 3. Now look at the three hypothetical (Hint: Think about Lesson 2, Birds of a Answers will vary but may include cladograms again. Taking one character from Feather?) internal anatomical features, embryological your table at a time, determine where a similarities and differences, DNA, rRNA, or character state change would have to occur protein sequence data, and behavioral to produce each species. Make a hatch differences. mark at each position on each hypothetical cladogram to indicate every character state 6. Which cladogram most likely explains the change. Answers will vary. evolutionary relationships of these gopher B Using the 4. Which hypothesis most likely explains the species? Explain your answer. concept of parsimony, this hypothesis phylogenetic history of these pocket gopher produces the gopher species with the least species using the six characters that you number of changes (8 hatch marks) based selected? Explain your reasoning. Answers will vary. upon DNA differences.

Cladograms Based Upon DNA Sequences

HYPOTHESIS A HYPOTHESIS B HYPOTHESIS C SPECIES SPECIES SPECIES I II III IV I III II IV I IV II III

12 Hatch Marks 8 Hatch Marks 12 Hatch Marks

ANCESTOR ANCESTOR ANCESTOR

7. Is it possible to have character data support a different hypothesis than the DNA data? Yes. Explain your answer. The hypothesis supported may depend upon which characters or DNA sequences are used. 8. Once the most likely cladogram has been determined for related species, this information could be used to make predictions about species. For instance, if a disease strikes gopher species I but not gopher species III, what would you predict about the resistance of gopher species II and IV to this same disease? Gopher species I and IV are closely related, so species IV is also likely

Lesson 5: The Pocket Gopher Cladogram Conundrum

66 The Species Question to be affected by the disease. Gopher What do the scientific names of these pocket species II and III are more closely related, gopher species imply regarding their phylo- so species II is most likely to be resistant genetic relationships? Species I and III to the disease. belong to the same genus (Thomomys), so they must be more closely related to each 9. How are morphological characters and other. DNA sequence data related? DNA codes for the different characters of an organism. 11. As more DNA sequences are accu- 10. The scientific names of the four gopher mulated, researchers gain better under- species are given below. standing of the phylogenetic relationships of organisms and may reassign the classification Species I—northern pocket gopher groups that organisms have previously been (Thomomys talpoides) assigned. Which classification groups are Species II—plains pocket gopher more likely to be changed, a general grouping (Geomys bursarius) (like kingdom or phylum), a specific grouping Species III—Botta’s pocket gopher (like genus or species), or an intermediate (Thomomys bottae) grouping (like orders or families) as DNA data Species IV—yellow-faced pocket gopher on species are evaluated? Any answer with (Pappogeomys castanops) support should be accepted because reas- signment of classification categories is occurring at all taxonomic levels.

Notes ______

______Lesson 5: The Pocket Gopher Cladogram Conundrum ______

The Species Question 67 Lesson 5 Student Page Pocket Gophers Of Colorado

I—Northern Pocket Gopher Fan Shaped Mound, Plug

High, Fan Shaped Mound, Plug II—Plains Pocket Gopher

Mound Beneath Bushes, Large, Fan Shaped Mound, Plug

III—Botta’s Pocket Gopher

IV—Yellow-faced Pocket Gopher Tunnel Core

Lesson 5: The Pocket Gopher Cladogram Conundrum

68 The Species Question Student Page Characters Of Colorado Pocket Gophers

Characters Of Colorado I—Northern II—Plains III—Botta’s IV—Yellow-faced Pocket Gophers Pocket Gopher Pocket Gopher Pocket Gopher Pocket Gopher Total Length 165–250 mm 180–300 mm 200–260 mm 245–300 mm Tail Length 45–75 mm 50–90 mm 60–85 mm 68–80 mm Hindfoot Length 25–31 mm 30–36 mm 28–33 mm 34–40 mm Ear Length 5–7 mm 3–5 mm 5–7 mm <7 mm Weight 100–150 grams 170–330 grams 110–215 grams 160–350 grams Body Color Dark brown or Pale brown to Yellowish to Reddish brown (Dorsal or Back) yellowish brown yellowish-brown reddish brown to grayish yellow; black patch behind ears Body Color Whitish Slightly paler than Slightly paler than Buffy (Ventral or Belly) dorsal dorsal Foot Color Whitish White Whitish Blackish Frontal Grooves on None 2 None 1 Incisors Mammae 10 6 8 6 Shape of Entrance Mound Fan shaped mound, High fan shaped Fan shaped mound, Mound beneath plug mound, plug plug bushes,large, fan shaped, plug Tunnel Cores? Yes No Yes No

Eye Size Observations: Lesson 5: The Pocket Gopher Cladogram Conundrum

Limb and Claw: Observations: Other Observations:

The Species Question 69 Student Pages The Pocket Gopher Cladogram Conundrum

co• nun• drum (k -n n’dr m) n. [Orig. unknown.] 1. A riddle in which a fanciful question is answered by a pun. 2. a. A problem with no satis- factory solution. b. A complicated problem. Webster’s II New College Dictionary, ©1995 Houghton Mifflin Company

In case you are wondering what this construct different possible cladograms lesson is about, look at Webster’s defi- using the steps you are already familiar nition “2.b.” for conundrum. Life can be a with. First, they determine some challenge, and it is certainly a challenge to observable characters (traits) and note figure out life—the diversity of life. As their “states.” A character state is one tricky as it might be to sort out evolu- of two or more possible forms for that tionary relationships of organisms that character. For example, for a character have very different features, such as “wings,” the possible states may be hippopotamuses and giraffes, it really gets “present” and “absent.” For the character difficult when the animals look nearly alike. “number of digits,” possible states may be Usually, a biologist has to start out with 1, 2, 3, 4, or 5. several predictions—hypotheses—and then choose the best one based on the The next step is to determine which most evidence. character states are ancestral and which are derived. Usually, this is done by Constructing a cladogram is the first comparing the group of organisms step in figuring out an organism’s (in-group) with a more distantly related phylogeny. Every cladogram represents a organism, the out-group. If the character hypothesis—a possible answer to the has only two states, then the task of questions “How are these organisms distinguishing ancestral and derived related?” and “How might this group of character states is fairly simple: The taxa have evolved from a single common character state which is in the out-group ancestor?” When relationships of very is ancestral and the one found only in the similar species are in question, biologists in-group is derived. For example, if the put together many different cladograms organism in the out-group does not have and then look at morphological and wings, and all the organisms in the genetic evidence to form an argument for in-group do have wings, then wings are or against each hypothesis. the derived character state. It can be a little more difficult to determine which character state is ancestral or derived when there are First Steps many possible states. Let’s consider the character “digit” as an example. On the To put together and sort through following page is a group of mammals several hypothetical cladograms for a listed with the number of digits for each: group of similar organisms, cladists

Lesson 5: The Pocket Gopher Cladogram Conundrum

70 The Species Question are homologous. The flippers of whales Number of Digits Mammal and dolphins look like and function like the (fingers or digits) pectoral fins of sharks. These body parts Human 5 resemble each other because whales, dolphins, and sharks live in the same Horse 1 environment and all need to be effective Cow 4 swimmers to obtain food and survive. The Rhinoceros 3 paddle-like flippers of whales and dolphins are highly modified hand bones, with five Giraffe 2 finger bones. The shark’s pectoral fins are supported by cartilage. Another example If scientists compare this group of would be the wings of a bird or the wings mammals with some out-group of of an insect. Both enable flight, but the terrestrial vertebrates—maybe crocodiles, structure and origin of the two kinds of turtles, or frogs—they can see that animals wings differ. Through the process called in these out-groups also have 5 digits on convergent evolution, similarities evolve each limbs, so “5 digits” must be the in organisms not closely related to one ancestral character state. another, usually because they live in similar habitat and have a similar way of life. Similarities that arise through convergent evolution are called analogous characters. More To Think About This takes us to the third step. To This brings up a problem, and it is not accomplish the task of creating plausible just which character state—1, 2, 3, or 4— cladograms, cladists must use good comes next. Clearly, humans have more in judgment. Good judgments are based on common with horses and giraffes than they asking good questions. Are characters do with crocodiles and frogs. Humans have chosen well? Should other or additional retained the ancestral character of “5 characters be considered? Could a digits” while the other mammals in this list supposed shared derived character (simi- have not. This character may not be very larity inherited from a common ancestor) valuable for constructing a cladogram for be the result of independent evolutionary these species. development (convergent evolution)?

Cladistics assumes that organisms that are more similar to one another than they Lesson 5: The Pocket Gopher Cladogram Conundrum are to other organisms are more closely Last Steps related. However, inferring relationships from similarities can be misleading. Not all After the cladist has finally decided homologous characters—those inherited which characters to use, he or she moves from a common ancestor—look similar. In on to the fourth step; building the data table Lesson 4, the various forelimbs of verte- of characters. When the data leads to brates, such as wings, flippers, arms, and several possible cladograms, scientists legs, were examples of homologous choose the most “parsimonious” cladogram. features that did not look alike. Using parsimony to evaluate conflicting cladograms is the fifth and final step. Also, just because characters or features look similar does not mean they

The Species Question 71 The rule of parsimony is that As a pocket gopher digs, it pushes soil any hypothesis that requires fewer behind itself. When enough loose material assumptions is a more defensible accumulates, the gopher turns around and hypothesis. What this means is that the shoves the dirt up to the surface with its cladogram that had the least number of chin and forefeet. The expelled dirt forms changes in character states is the most large fan-shaped mounds. Pocket gophers logical. In other words, the best cladogram plug the opening to these mounds so that is the one that minimizes the number of weasels and snakes cannot get in and times a feature must be assumed to have hunt them underground. arisen or disappeared. Pocket gophers tunnel to get food, Speaking of assumptions, this author mainly green vegetation and roots. thinks you may need to see an example of Usually, they eat in their burrows, often choosing between cladograms using pulling entire plants underground. When parsimony to make sense of this. So, we’ll they feed at the surface, pocket gophers get to that pretty soon. First, you need to clip off vegetation around the burrow as know a thing or two about pocket far as they can reach without losing gophers. physical contact with the tunnel opening.

Now take a look at the page: Characters of Colorado Pocket Colorado’s Pocket Gophers Gophers. In addition to the characters listed on the table, all four species of You should have in your possession pocket gopher share these characters: two important pages: Pocket Gophers of rodent shape, external fur-lined cheek Colorado and Characters of Colorado pouch, short hairless tail, long claws on Pocket Gophers. Take a look at the toes, four toes on forelimbs, five toes on pictures on the page: Pocket Gophers of hind limbs and 20 teeth. These characters Colorado. The pictures show Colorado’s were probably shared by some ancestor four species of pocket gopher and some that all four species have in common. evidence that one could find that they live in a certain habitat. These rat-sized Your Task rodents are named for the external, fur- Please use the last three rows of the lined storage pouches on each cheek. table to fill in characters that you observe Pocket gophers are well-suited for life by looking at the illustrations of the four underground. Rarely seen, they excavate species of pocket gopher. extensive underground tunnel systems with numerous forks and special side branches for stockpiling food, nesting, and storing feces. They have short tails, tiny Getting in the Groove eyes, dinky ears, and strong front legs with claws for digging. Their lips close Using the principle of parsimony, let’s behind their ever-growing incisors, so evaluate three possible pocket gopher gophers can dig with their teeth without cladograms using only one character getting a mouthful of soil. “Frontal Grooves on Incisors.” For this example, we will say that the ancestral character is “no frontal grooves.” Each

Lesson 5: The Pocket Gopher Cladogram Conundrum

72 The Species Question time the character state must be changed on the proposed cladogram, we will make a hatch mark on the branch on the cladogram where the change occurs.

HYPOTHESIS A HYPOTHESIS B HYPOTHESIS C SPECIES SPECIES SPECIES I II III IV I III II IV I IV II III

ANCESTOR ANCESTOR ANCESTOR

In Hypothesis A cladogram, there In Hypothesis B cladogram, assuming would need to be a change that caused the ancestor had no frontal grooves on its grooves to form on the incisors where the incisors, there would be one change in two new lineages occur. The branch to character state on the branch to species II species I and II would need to show the and IV, which each have frontal grooves. development of two frontal grooves and Then, because the branch to species II the branch to species II and IV would would need to indicate a change from one need to show the development of one frontal groove to two frontal grooves, there frontal groove. So, both branches would would be another hatch mark on that have a hatch mark. Then, since species I branch. Hypothesis B has two character has no frontal groove, there would need to state changes, indicated by two hatch be another change in character state marks. showing the loss of the two frontal grooves where that species branches off. According to the principal of

That change would also be indicated with parsimony, Hypothesis B most likely Lesson 5: The Pocket Gopher Cladogram Conundrum a hatch mark. A similar change would also indicates the true phylogeny—evolu- happen on the branch to species III, tionary relationship—of the four species of showing the loss of one frontal groove. pocket gopher if only the one character Altogether, for the character “Frontal was considered. Of course, cladograms Grooves on Incisors,” there would be four are rarely constructed soley on the basis changes in character state for Hypothesis of just one character. A. Hypothesis C would also show four changes in character state, designated by four hatch marks.

The Species Question 73 Now It's Your Turn 1. Look at the table Characters of Colorado Pocket Gophers again. Looking at the characters that have been I—Northern Pocket provided and the characters you Gopher observed, choose six characters that you believe might have the most impact on the day to day survival and reproduction of the four species of pocket gopher. Explain why you believe the six characters that you selected would help a pocket gopher adapt to its environment. ______II—Plains Pocket ______Gopher ______

2. Place the six characters in the table below and indicate the “state” for the character for each species. Pocket Gopher Characters Gopher Species Character I II III IV

Lesson 5: The Pocket Gopher Cladogram Conundrum

74 The Species Question 3. Now look at the three hypothetical cladograms again. Taking one character from your table at a time, determine where a character state change would have to occur to produce each species. Make a hatch mark at each position on each hypothetical cladogram to indicate every character state change.

HYPOTHESIS A HYPOTHESIS B HYPOTHESIS C SPECIES SPECIES SPECIES I II III IV I III II IV I IV II III

ANCESTOR ANCESTOR ANCESTOR

4. Which hypothesis most likely explains 5. What other types of characters, the phylogenetic history of these pocket besides external appearance, could be gopher species using the six characters used to construct a data table and a that you selected? Explain your cladogram? (Hint: Think about Lesson 2, reasoning. Birds of a Feather?) ______

______Lesson 5: The Pocket Gopher Cladogram Conundrum ______

III—Botta’s Pocket IV—Yellow-faced Gopher Pocket Gopher

The Species Question 75 Cladogram Or Phylogenetic Tree? Cladograms Based Upon DNA In practice, when cladograms are Sequences constructed, many hundreds of characters It can be very difficult to sort out have to considered, and computers are evolutionary relationships of similar needed to sort out which organisms go species based on physical characters on each branch. An advantage of cladistics alone. It is not always obvious which is that it is a very objective analytical traits are the most important. Molecular technique. If a data table containing the biological technologies have been very same set of character data is fed into helpful in determining phylogeny. We can and analyzed repeatedly by different now compare the sequences of DNA, RNA computers, the computers will construct or proteins which are more representative identical cladograms each time. Cladistic of fundamental genetic relationships than analysis simply indicates if a character are many superficial physical characters. exists or not, and then determines the sequence or order in which derived char- How are molecular cladograms acters arose. constructed? First, the biologists need to decide which molecule to compare. While A disadvantage of cladistics is that it cladists can compare sequence portions does not consider the importance of any of cellular DNA or the mitochondrial DNA, one character. Equal weight is given to all they usually sequence ribosomal RNA the characters used and some of them may (rRNA). All living cells must make proteins be fairly insignificant. In contrast, when and so all cells have ribosomes. The rRNA biologists use evolutionary systematics, molecule is usually not as large as the they weight or give more importance to entire DNA molecule. some derived characters over others. This is what you just did when you selected six After DNA or rRNA sequences are characters that you thought would be more determined for each organism, the important to the survival and reproduction sequences are aligned and compared. of pocket gophers! As another example, a This task is usually done by computers biologist using evolutionary systematics that can sort through the differences and principles would probably consider the construct cladograms. Closely related character “giving birth to live young” species will have fewer differences in the more important than “fur color” when DNA or RNA sequences than species that considering the evolutionary relationships are more distantly related. of placental mammals and monotremes (i.e. duck-billed platypus). The following table shows differences in DNA sequences for the gopher species The branching diagram that is at different locations for the same gene. constructed when a scientist uses Use this information the same way that subjective judgment when deciding which you used physical characters to determine characters to weight the most heavily are which hypothetical cladogram best called phylogenetic trees. A phylogenetic describes the most likely evolutionary tree and a cladogram are similar in that history for these gophers. Taking one DNA each represents a hypothesis of evolu- difference at a time, place a hatch mark (/) tionary history, but phylogenetic trees show at each position on each hypothetical both the best judgment and the biases that cladogram where a change or mutation the scientist may have.

Lesson 5: The Pocket Gopher Cladogram Conundrum

76 The Species Question would have to occur in order to produce the four gopher species. Gopher DNA Sequence Differences Pocket Gopher Site of DNA Change Species 1 2 3 4 5 6 7 8 IACCGGCGC II A T G A A C A G III A C G G G T G C IV G T G G A C A G

HYPOTHESIS A HYPOTHESIS B HYPOTHESIS C SPECIES SPECIES SPECIES I II III IV I III II IV I IV II III

ANCESTOR ANCESTOR ANCESTOR

6. Which cladogram most likely explains 7. Is it possible to have character data the evolutionary relationships of these support a different hypothesis than the gopher species? _____. Explain your DNA data? _____. Explain your answer. answer. ______Lesson 5: The Pocket Gopher Cladogram Conundrum ______

The Species Question 77 8. Once the most likely cladogram has 10. The scientific names of the four gopher been determined for related species, species are given below. this information could be used to make Species I—northern pocket gopher predictions about species. For instance, if (Thomomys talpoides) a disease strikes gopher species I but not Species II—plains pocket gopher gopher species III, what would you predict (Geomys bursarius) about the resistance of gopher species II Species III—Botta’s pocket gopher and IV to this same disease? (Thomomys bottae) ______Species IV—yellow-faced pocket ______gopher (Pappogeomys castanops) ______What do the scientific names of these ______pocket gopher species imply regarding ______their phylogenetic relationships? ______9. How are morphological characters and ______DNA sequence data related? ______11. As more DNA sequences are accu- ______mulated, researchers gain better understanding of the phylogenetic relationships ______of organisms and may reassign the ______classification groups that organisms ______have previously been assigned. Which ______classification groups are more likely to be changed, a general grouping (like kingdom ______or phylum), a specific grouping (like genus or species), or an intermediate grouping (like orders or families) as DNA data on species are evaluated? ______

Lesson 5: The Pocket Gopher Cladogram Conundrum

78 The Species Question Notes ______

______Lesson 5: The Pocket Gopher Cladogram Conundrum ______

The Species Question 79 Lesson 6 Educator’s Overview Déjà Vu

Summary Students read and analyze a recent study completed by the University of Colorado for the Colorado Division of Wildlife to determine if a particular population of pocket gophers is a subspecies in need of special protection, or just a variation of a very common species.

Duration Learning Objectives Background One 45-minute After completing this activity, Speciation occurs when a class period students will be able to: descendant population can no • Describe the application of longer interbreed with the cladistics to a current wildlife ancestor population. Species management issue. undergo different selective Vocabulary pressures in different envi- • Review and evaluate a research Candidate species ronments. Small, isolated popu- paper and describe its signif- lations of species may, over time, Divergence icance. develop noticeably different Genetic Drift • Provide examples of how peer physical features in response to Home Range review improves scientific their environment than similar inquiry. populations elsewhere. Are Niche these changes indicative of a Peer review significant modification of the Speciation species? Do differences in appearance indicate the Species of special presence of a subspecies or concern new species? How small or big Subspecies of a change is significant. These questions are important ones for biologists who are trying to quantify and maintain species diversity.

Cladistics has been especially useful as a tool for scientists working with these questions. This activity ties together all the concepts found in The Species Question, and demonstrates how cladistics is used to address current wildlife issues in Colorado.

Lesson 6: Déjà Vu

80 The Species Question Teaching Strategies knowledge; and the findings. The importance of peer review to 1. Thoroughly read the student the scientific “way of knowing” materials for Déjà Vu. can never be overemphasized. Please use this web site to show 2. Give each student the reading students examples of peer packet, Déjà Vu. review: 3. After giving students http://mountain-prairie.fws.gov/ sufficient time to read the packet, preble/PEER/PEERindex.htm review the need for a legal definition of species. Wildlife managers and others must make decisions and take actions to maintain healthy Assessment populations of organisms and their habitat. In order to avoid Ask students to write a short confusion and possibly court paper which describes the battles, they need to agree on relevance of taxonomy and what populations need systematics to wildlife protection. management. 4. Ask students to describe how taxonomy and cladistic analysis Materials and contribute to wildlife conser- Preparation vation. Cladistic analysis makes Extension it possible to evaluate the Divide the class into groups • Student Reading Pages Déjà Vu— morphological and genetic of three and ask each group to differences between various one photocopy review and comment on one of per student wildlife populations. This helps the scientific studies concerning identify populations that are the genetic uniqueness of • Access to the unique and in need of Preble’s meadow jumping mouse library and the internet protection. at: 5. Peer review is essential to the http://mountain-prairie.fws.gov/ process of scientific inquiry. In preble/ communicating and defending Student groups should look the results of scientific inquiry, at the study and the peer review arguments must be logical and of the study. If time allows, demonstrate connections students can debate both sides between the methods and of the Preble’s argument. procedures used; the historical body of scientific

Preble’s Meadow

Jumping Mouse Lesson 6: Déjà Vu

The Species Question 81 Key 4. How many mtDNA samples were taken for analysis for the subspecies report? 24 1. To which pocket gopher species did the 5. Why were museum specimens used? If three subspecies listed in the study (T.t the subspecies was indeed threatened or rostalis, T.t. retrosus, and T.t. macrotis) endangered, it would not be reasonable to belong? Thomomys talpoides trap more animals out of the population for 2. The authors of the report state that the testing. subspecies T. t. macrotis was named on 6. How long are the mtDNA sequences being morphological grounds. What does that tested? 296 bases mean? Scientists based the classification of T. t. macrotis on physical characteristics 7. What species was chosen to represent the which could be observed. out-group? Why is an out-group used? The thirteen-lined ground squirrel was chosen 3. When was the taxonomy of Colorado to represent the out-group. An out-group is pocket gophers last revised? What new not closely related to the animals being technology has been developed since that studied and is used to compare the time to assist taxonomists in determining the differences between the animals. taxonomy and phylogeny of pocket gophers? The taxonomy was last revised in 1915. Since then, computers and molecular biology techniques have been developed that allow biologists to compare DNA and RNA sequences.

Lesson 6: Déjà Vu

82 The Species Question Notes ______

______Lesson 6: Déjà Vu ______

The Species Question 83 Lesson 6 Student Pages Déjà Vu

Caution: Much of what you are about Wildlife on either the state or federal to read will sound eerily familiar. You may lists requires more intensive management. have the feeling that you have read these Some management techniques to prevent lines before. Rest assured that nothing the extinction of species or subspecies paranormal is happening—bits and pieces have considerable social and economic of the last five lessons are being repeated impacts. The ESA may limit land use or to so that you will see the BIG PICTURE human activities in habitat considered and will understand how all of these ideas important to threatened or endangered connect with wildlife conservation. The species. For this reason, it is important BIG PICTURE joins together three smaller that listing decisions are made with the pictures from past lessons. best available scientific information.

In order to be consistent and accurate, wildlife managers use a legal definition of Small Picture #1 species for decisions to list certain populations as threatened or endangered. The In Lesson 1, you learned that the four characteristics of populations that Colorado Division of Wildlife (DOW) is the would be used to consider the population state agency responsible for protecting unique include: and managing Colorado’s wildlife and 1. Usually do not interbreed with other habitat. The biologists at the DOW abide populations; by both state and federal wildlife laws. 2. Have different appearance, behavior, One of the most significant of all of the or ecological niche than other popu- laws is the Endangered Species Act (ESA) lations; of 1973. Both the state and federal government maintain a list of threatened 3. Have notably different DNA (genetic and endangered species and also a list of material that determines inherited char- species at risk of becoming threatened or acteristics); and endangered. At the state level, these are 4. Represent a unique evolutionary species of special concern. At the lineage and contain the potential for a federal level, these species are often unique evolutionary future. candidate species for possible listing. In Lesson 2, you discovered that two Species on the State of Colorado’s populations of sage grouse that biologists threatened and endangered list are once thought belonged to the same managed by the DOW. When a species is species were really two different species. placed on the federal threatened or There was undeniable evidence that the endangered species list, the federal two populations did not interbreed, government, through the U.S. Fish and differed in appearance, behavior and Wildlife Service, supersedes the state’s niche, and had different DNA. Lesson 2 authority to manage that species.

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84 The Species Question did not address the fourth requirement Small Picture #3 that each population represent a unique evolutionary lineage—this one will! In Lessons 4 and 5, you developed a basic understanding of cladistics and how this system of analysis helps biologists understand the evolutionary relationships Small Picture #2 of all living things. Each branch of a cladogram represents a unique lineage of In Lesson 3, you learned that ideas organisms that share unique traits or char- and methods about classifying species acters. Cladistic analysis allows wildlife and figuring out species relationships to biologists to address the fourth part of the one another have changed over time. legal species definition, that the popu- Classification schemes change for a lation represent a unique evolutionary number of reasons. First is that, over time, lineage and contain the potential for a people develop different world views, they unique evolutionary future. have new ideas. Some new ideas take thousands of years to develop. A second reason taxonomic classifications change is that scientists have new Speciation data. Consider the sage grouse example. Biologists began collecting more physical When biologists speak of a population and behavioral data about the birds. In containing the potential for a unique addition, a new technology, DNA and RNA evolutionary future, they mean that the sequencing, provided new sources of population may be genetically unique character information or data to compare. enough to be undergoing speciation, the This information made it clear that the two process by which new species form. populations of birds were very different Species formation occurs in stages and is from each other. New information a very slow process. reveals new similarities and differences among groups that may cause taxon- Separate populations of a single omists to revise a group’s classification. species can live in different types of environments. In each of these environments, Another reason that classification there are different “selective” pressures, schemes change is that biologists find conditions that challenge the survival of new species. Over time, humans have the population. Often, various populations explored more of Earth’s environments. of species overlap and interact and Often, unique organisms are found in deep continue to exchange genes by breeding. ocean vents, high alpine tundra, caves However, some populations can become and other newly searched places. isolated from other populations of their As previously unknown species are species. Over time, animals that are able discovered, classifications also change to to survive and reproduce pass their char- include them. acteristics to young that are genetically better adapted to the unique environment that they live in. Genetic differences between the groups accumulate slowly over time, a process called divergence, or Lesson 6: Déjà Vu genetic drift. Over time, populations of

The Species Question 85 the same species that have notable trees—girdling or clopping stems and genetic difference because of adaptations pruning roots. They can decimate a prized to certain living conditions become what flower garden. Many homeowners and biologists call subspecies. The members agricultural producers both past and of the newly formed subspecies have present have worked on eradicating taken the first step toward speciation. gophers from their property. Eventually, the subspecies may become so different that they can no longer In March of 2003, two conservation interbreed successfully with other popu- groups filed an emergency Endangered lations. Biologists then consider then Species Act listing petition for the Douglas different species. County pocket gopher (Thomomys talpoides macrotis), seeking to list the pocket gopher as endangered. Their claim was that uncontrolled sprawl in Douglas Back To Pocket Gophers County had brought the pocket gopher to the brink of extinction, that its habitat had Pocket gophers are one group of been paved over for parking lots, car deal- animals that seem particularly susceptible erships, and other developments. The to genetic drift. They have very small pocket gopher of concern was thought to home ranges—the area where they live survive in only five populations in Douglas and travel. Often, pocket gophers live their County. entire lives in one burrow system that occupies less than half an acre. Pocket If the pocket gopher was listed as gophers live solitary lives, except briefly endangered, the decision would have a during the breeding season. They are very huge economic impact on Douglas territorial and carefully avoid encounters County. As the state agency responsible with each other. When they do meet, for wildlife management, the DOW enlisted they fight ferociously. For these reasons, geneticists at the University of Colorado to pocket gophers adapt to their local envi- explore the classification of these pocket ronment over many generations, and seem gophers to determine if they were indeed to diverge into subspecies and species a unique subspecies needed special more quickly than other kinds of protection. A portion of the final report of mammals. the scientists demonstrates the use and importance of Like every wildlife species, people cladistics in have varying “situational” viewpoints addressing current about pocket gophers. In their natural wildlife problems. environment, pocket gopher burrowing is Here is the first viewed as beneficial. They increase soil section of the report: aeration and water infiltration, and boost soil fertility. Pocket gopher burrows also provide hibernation sites and summer retreats for salamanders, frogs, and toads.

In other situations, pocket gophers are viewed as pests. Pocket gophers love alfalfa and can be destructive to crops and

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86 The Species Question and it is geographically isolated from T. t. Final Report rostralis, which occupies the mountains to Genetic relationships among the west, and T. t. retrorsus, which occupies the Palmer Divide to the south and east. subspecies of Thomomys talpoides: T. t. macrotis, T. t. macrotis was named on morpho- T. t. rostralis, T. t. retrorsus logical grounds by F. W. Miller in 1930. The subspecies was characterized by generally Jeffry B. Mitton larger size and paler, more grayish color than Renee Culver adjacent populations. However, there has Department of Ecology and Evolutionary been no taxonomic revision of Thomomys Biology talpoides since 1915, and prior to this study, University of Colorado no genetic data have been collected to Boulder, CO, 80309 evaluate the phylogenetic relationships among the subspecies. Human population growth and development in the greater The northern pocket gopher, Thomomys Denver area make this a propitious time to talpoides, is a polytypic species with evaluate the subspecific designation of numerous described subspecies, nine of macrotis. Recently, the Colorado-based them within Colorado (Armstrong, 1972). T. t. Center for Native Ecosystems and Arizona’s macrotis is ascribed a range in Douglas, Forest Guardians filed a petition with the U. Elbert and Arapahoe Counties. The S. Department of the Interior to list T. t. geographic distribution of macrotis is small, macrotis as threatened or endangered.

1. To which pocket gopher species did 3. When was the taxonomy of Colorado the three subspecies listed in the study (T.t pocket gophers last revised? What new rostalis, T.t. retrosus, and T.t. macrotis) technology has been developed since that belong? time to assist taxonomists in determining ______the taxonomy and phylogeny of pocket gophers?

2. The authors of the report state that the ______subspecies T. t. macrotis was named on ______morphological grounds. What does that ______mean? ______

______Lesson 6: Déjà Vu ______

The Species Question 87 It is nearly impossible to rely on physical traits to We proposed to use mitochondrial DNA (mtDNA) to classify subspecies. In examine the variation within and among these three order to have defensible subspecies. Specifically, we proposed to examine the evidence to make following questions: management decisions 1) Is T. t. macrotis genetically distinct from T. t rostralis, about T. t. macrotis, the and T. t. retrorsus? researchers decided 2) What is the magnitude of the genetic differences that mitochondrial DNA among these subspecies? sequencing was necessary. 3) Given the genetic differences among other recognized subspecies of the northern pocket gopher, is there sufficient justification for subspecific status of T. t. macrotis?

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88 The Species Question Here is the procedure the researchers used:

We obtained DNA samples by clipping CU’s University Museum and the Denver small pieces of skin from dried museum Museum of Nature and Science. samples. The samples were taken from the

Specimen sampled for a molecular systematic study of three subspecies in Thomomys talpoides.

T. t.rostralis D5833 Jefferson County, Brookvale, Evergreen D7627 Park County, 19km N, 11km E Salida; Herring Creek D9022 Park County, 1mi W of Porcupine Cave, 9100ft D9023 Park County, 1mi W of Porcupine Cave, 9100ft D10466 Jefferson County, Connifer, 10647 Snowy Trail 5073 Boulder County, Long Canon, Green Mountain 11376 Larimer County, Rist Canyon 17.5mi NW Ft Collins T8N, R71W, sec26 13991 Clear Creek County, Headwater Clear Creek 14284 Grand County, Steelman Creek T.t.macrotis D4428 Douglas County, D'Arcy ranch; 2mi N Parker 17010 Russelville Rd .5mi SE Reed Hollow 17012 Douglas County, Along road to McArthur Ranch T6S, R67W, sec19 17013 Douglas County, Along road to McArthur Ranch T6S, R67W, sec19 17015 Douglas County, Willow Creek at County Line Rd T6S, R67W, sec4 17016 County Line Rd 2mi W of Willow Creek 17017 Douglas County, E of Grand View Estates T6S, R67W, sec12 T.t.retrorsus 17005 El Paso County, 2mi E of I-25 on Palmer Divide Rd 17006 Douglas County, E of upper E Cherry Creek T10S, R65W, sec28 17007 Douglas County, Palmer Gulch Rd 3.25 mi E I-25, roadside ditch 17008 Douglas County, Lake Gulch T9S, R66W, sec4 17009 Douglas County, E of upper E Cherry Creek T10S, R65W, sec33 17011 Douglas County, McMurdo Gulch Rd, .3mi W Cherry Creek T7S, R66W, sec27 17019 Douglas County, E Cherry Creek T10S, R65W, sec9 17020 Douglas County, E Cherry Creek T10S, R65W, sec9

Note: D indicates samples from the Denver Museum of Nature and Science.

We obtained mitochondrial cytochrome submitted to GenBank. The sequences are oxidase I (COI) sequences from seven T. t. 296 base pairs long, and 40 of the nucleotide macrotis, nine T. t. rostralis, and eight T. t. sites are variable.

retrorsus, and these sequences are being Lesson 6: Déjà Vu

The Species Question 89 4. How many mtDNA samples were taken for analysis for the subspecies report? ______

5. Why were museum specimens used? ______

6. How long are the mtDNA sequences being tested? ______Imagine the task of constructing all the possible cladograms comparing this may DNA sequences! This would boggle the best of minds, so the scientists used a computer to sort the mtDNA bases and produce a cladogram:

A neighbor joining tree of mtDNA sequences from Thomomys talpoides rostralis, T. t. macrotis, and T. t. retrorsus, with Spermophilus tridecemlineatus as an out- group. A neighbor joining tree summarizes the relationships among the 24 COI sequences, using the thirteen-lined ground squirrel as an out-group. The data are based on 296 bases from the mitochondrial gene for cytochrome oxidase I. (Specimens marked with an asterisk might have been identified incorrectly).

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90 The Species Question Lesson 6: Déjà Vu

The Species Question 91 The results of the research were as follows:

The mtDNA sequences do not form three groups corresponding to subspecies, but are all intermixed, with no evidence of subspecific groups at all. That is, the mtDNA do not support the subspecific appellations in the literature. The three recognized subspecies have geographically distinct ranges, and differ morphologically, but their mitochondrial lineages have apparently not had sufficient time for lineage sorting and/or selection to develop reciprocal monophyly.

We can now repeat the questions that we proposed to address, and provide answers (in bold).

1) Is T. t. macrotis genetically distinct from T. t rostralis, and T. t. retrorsus? No 2) What is the magnitude of the genetic differences among these subspecies? There are no discernible groups, the subspecies are intermixed in the tree. There are no diagnostic differences among the three subspecies. 3) Given the genetic differences among other recognized subspecies of the northern pocket gopher, is there sufficient justification for subspecific status of T. t. macrotis? MtDNA sequences do not support the subspecific designations of T. t. rostralis, T. t. retrorsus, and T. t. macrotis.

7. What species was chosen to represent The scientists found “no discernable the out-group? Why is an out-group used? groups”—they did not find enough genetic differences to classify T.t. macrotis as ______a subspecies. How did their findings ______affect the petition to list this species as ______threatened or endangered? The U.S. Fish ______and Wildlife Service reviewed the petition ______to list the pocket gopher in Douglas County, Colorado, and, with this infor- ______mation, concluded that listing the Douglas ______County pocket gopher was not necessary. ______The negative finding was published in the ______Feb. 14, 2006; Federal Register, pages 7,715–7,720 and you may read the entire decision at this web site: http://a257.g.akamaitech.net/7/257/2422/ 01jan20061800/edocket.access.gpo.gov/ 2006/06-1288.htm

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92 The Species Question Back to the Future February 2, 2005, based on Ramey’s study, the U.S. Fish and Wildlife Service Species questions are important. If (USFWS) issued a 12-Month Finding on species are threatened or endangered, a petition to delist the Preble’s and steps must be taken to protect them. proposed to remove the mouse from the At the same time, if a population only Federal list of threatened and endangered appears to be unique and is not, agencies species. would not want to devote scarce time and resources to management efforts for it. Seeking to use the best science possible in making a final decision, the Sometimes it is difficult to determine Service later commissioned Dr. Tim King what the status of a particular group of of the U.S. Geological Survey (USGS) to animals is. As this booklet of lessons is do an independent genetic analysis of being published, there is lots of scientific several meadow jumping mouse debate about the status of a little mouse. subspecies. The USGS study results, Preble’s meadow jumping mouse (Zapus provided to the Service on January 25, hudsonius preblei) is a small rodent 2006, raised significant questions about approximately 9-inches in length with large the conclusions drawn by Dr. Ramey in his hind feet adapted for jumping. Its long, study. bicolor tail accounts for 60 percent of its length and it has a distinct dark stripe Because of the complexity of this down the middle of its back that is issue, the Service extended for six months bordered on either side by gray to orange- its proposal to delist the Preble’s meadow brown fur. jumping mouse. A six-month extension in making final determinations on listing or This shy, mostly nocturnal mouse lives delisting proposals is allowed under the in some of the most desired real estate in Endangered Species Act in situations the west. It prefers heavily vegetated where there is substantial disagree- streamside and adjacent upland habitat ment regarding the sufficiency or along the foothills of the Front Range, accuracy of the available data. from southeastern Wyoming south to Colorado Springs, Colorado. This area has Since Dr. Rob Roy Ramey and Dr. Tim undergone rapid residential, commercial, King disagreed on whether the Preble’s agricultural, and industrial development, to meadow jumping mouse constituted a the detriment of the mouse. valid subspecies, the studies were placed on the USFWS Web site for public On May 13, 1998, Preble’s meadow comment and peer review. Peer review jumping mouse was designated as is a process of subjecting a scientist’s threatened by the U.S. Fish and Wildlife work or ideas to the scrutiny of others Service in its entire range. Many people’s who are experts in the field. Peer review is livelihoods were affected by this decision an essential component of the science and it was just a matter of time before process, and all scientists typically more studies were done on the mouse. recognize that cherished data, analyses and interpretation may ultimately be over- Genetic research conducted by Dr. turned by new information. The Service Rob Roy Ramey, formerly of the Denver also convened an expert panel of Lesson 6: Déjà Vu Museum of Nature and Science, ques- scientists to analyze, assess, and weigh tioned the uniqueness of the mouse. On the reasons why the conclusions of King

The Species Question 93 differed from the conclusions of Ramey. site. What will the outcome be? Will All of the genetic studies, peer reviews, there be scientific consensus to make a public comments, and results of the decision? Is Preble’s meadow jumping panel can be found at the U.S. Fish and mouse a valid subspecies? A decision Wildlife Service web site: may be made by the time you read this, http://mountain-prairie.fws.gov/preble or maybe more studies will be needed. In any case, the decision about Preble’s You can follow the decision-making meadow jumping mouse is sure to make process as it occurs by visiting this Web a few headlines!

Notes ______

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94 The Species Question Glossary

Analogous character: physical traits similar Clade: a group of organisms which includes in form or function, in two or more the most recent common ancestor of all of organisms that are not closely related, that its members and all of the descendants of evolved through convergent evolution that most recent common ancestor, a monophyletic group Ancestor: any organism, population, or species from which some other organism, Cladist: a biologist who uses cladistics to population, or species is descended by reconstruct the common ancestry rela- reproduction tionships among organisms Ancestral character: a trait or characteristic Cladistics: a method of analysis that attempts that many clades have in common and to classify organisms by common ancestry that was present in an ancestor of the Cladogram: a branching diagram, resulting clades from a cladistic analysis, that represents a Artiodactyls: even-toed ungulates with two or hypothesis about the order in which four toes organisms evolved Avian: bird Classification system: a method of grouping organisms Binomial: two names, the scientific name of an organism, the first name indicates the Five kingdom classification system: genus and the second the unique species groups species on the basis of cell name structure, body structure, and manner of getting energy or nourishment into five Biodiversity: biological diversity, including the kingdoms—Monera, Protista, Plantae, variety of species, the genetic differences Fungi, Animalia within species, and the variety of ecosystems. Three domain classification system: groups organisms on the basis of the Brachydont: low-crowned molars genetic makeup of their ribosomal RNA Bunodont: squarish molars with low rounded into three domains—Bacteria, Arcaea, and cusps Eukarya Two-empire classification system: Candidate species: federal designation for groups organisms based on cell structure species that are at risk of becoming into two empires—Prokarya or Eukarya threatened or endangered Clone: an organism produced by asexual Canines: dog-like species OR sharp teeth reproduction that is genetically identical to used to stab and hold prey its parent Cannon bone: in ungulates, the 3rd and 4th Convergent evolution: the independent metapodials may be fused to form a evolution of similar structures in distantly single, stronger bone related organisms, usually because they Carpal: measurement form the wrist bone of live in similar habitat and have a similar the wing to the tip of the longest primary way of life feather Culmen: straight-line measurement from the Character: identifiable feature, trait or charac- base to the tip of the upper beak teristic Derived character: a unique characteristic or Character state: one or two or more possible trait of a particular group of organisms Glossary forms of a particular character or trait

The Species Question 95 Diastema: toothless gap between incisors Home range: an area where an animal lives and premolars and travels in the scope of its normal activities Digits: fingers or toes Homologous characters or structures: Digitigrade: a foot posture in which the digits organs and body parts which are alike in are in contact with the ground when structure and origin walking or running, but not the sole or heel of the foot Hybrid: the fertile or infertile offspring of normally reproductively isolated popu- Distinct Population Segment: a category lations used by the Endangered Species Act (ESA) to denote populations that must be Hypsodont: high-crowned molars protected under the act; constitutes a Incisors: teeth at the front of the mouth legal definition of species In-group: in a cladistic analysis, the groups of Divergence: genetic drift, genetic differences organisms which are hypothesized to be between populations that accumulate closely related to each other slowly over time Lek: strutting grounds for breeding sage DNA (Deoxyribonucleic Acid): the material grouse that contains the information that determines inherited characteristics Marine: ocean Endangered: at risk of becoming extinct Mesaxonic: type of foot structure where the throughout all or a significant portion of its line of symmetry passes through the range center digit (toe), which is enlarged and bears most of the weight Endangered Species Act (ESA): a federal law passed in 1973 that seeks to prevent Metacarpals: hand bones that connect to the plants and animals from becoming extinct fingers in the United States Metapodials: metacarpals (hand bones) and Eukaryote: an organism made up of cells that metatarsals (feet bones) have a nucleus enclosed by a membrane Metatarsals: foot bones that connect to the Evolutionary systematics: modifying the toes process of cladistics by placing more “weight” or importance on certain derived Molars: cheek teeth located at the rear of the characters mouth behind the premolars Game: wildlife species that people can legally Molt: drop and replace feathers hunt, fish, or take Monophyletic group: members of a group Gene: a segment of DNA that is located in a which have characteristics in common chromosome and codes for a specific because they evolved from a common hereditary trait ancestor Gene Sequencing: determining the order of Morphological: physical form and structure the DNA bases in a gene Morphological trait or character: physical Genetic drift: divergence, genetic differences feature of an organism between populations that accumulate Natural selection: sometimes referred to as slowly over time “survival of the fittest,” the process by Genus: a group of similar species which individuals that are better adapted to their environment survive and Herbivorous: eats plants reproduce more successfully than less well-adapted individuals and pass their traits to their offspring, gradually changing Glossary the characteristics of the population 96 The Species Question Niche: the ecological role of an organism, the Scientific name: the binomial of a species, set of resources it consumes and habitats the first name indicates the genus and the it occupies second the unique species name Out-group: in a cladistic analysis, a group Selection: in agriculture, a process of which is not closely related to the groups choosing animals or plants to propagate, of organisms being studied and which is with the result that the inherited traits of used for comparison the chosen organisms are enhanced and perpetuated Reproductive isolation: populations of organisms that cannot breed and Selenodont: molars that have hard enamel reproduce due to some barrier or factor ridges running from back to front Paraxonic: type of foot structure where the Speciation: the process by which new line of symmetry passes between the two species arise centermost toes, which bear the body’s Species concept: a working definition of weight species Parsimony: refers to a rule used to choose Biological species concept: a group among possible cladograms, which states of organisms that is genetically similar that the cladogram implying the least enough to breed and produce viable and number of changes in character states is fertile offspring are considered a species the best Ecological species concept: organisms Peer review: a process of subjecting an which occupy the same niche are author’s scholarly work or ideas to the considered a species scrutiny of others who are experts in the field. Isolation species concept: groups of interbreeding natural populations that are Perissodactyls: odd-toed ungulates having reproductively isolated from other such either one or three weight-bearing toes groups are considered a species Phylogeny: an organism’s evolutionary history Morphological or Phenetic species concept: organisms with the same Phylogenetics: the study of the pattern of physical traits are considered a species events that have led to the distribution and diversity of life Species of special concern: Colorado’s designation for species that are at risk of Phylogenetic tree: a graphical representation becoming threatened or endangered of the interrelationships and evolutionary history of a group of organisms, which Stance: how an animal stands includes both the best judgment and Strata: layers of earth biases of the scientist Subspecies: a population of a species whose Plantigrade: a foot posture in which the full members have certain physical and length of the foot, including the heel, hereditary characteristics that distinguish it touches the ground from other populations of the species Premolars: cheek teeth in front of molars Systematics: the field of biology that deals Prokaryote: an organism lacking nucleated with the diversity of life cells Tarsals: bones in the fingers and toes Reproductive Isolation: barriers or factors Tarsus: measurement from the point where that prevent one population from inter- the leg joins the middle toe to the first joint breeding with another population in the leg

Ruminant: ungulate with a complex gut Glossary which helps it digest plants

The Species Question 97 Taxa: groups of organisms Uniformitarianism: the idea that the earth was shaped entirely by slow-moving Taxon: a group of organisms forces acting over a very long period of Taxonomy: the science of naming and clas- time sifying organisms Wildlife: (Colorado Statutes) all non-domestic Terrestrial: land mammals, birds, fish, amphibians, reptiles, mollusks, and crustaceans Threatened: species not in immediate peril of extinction, but likely to become Wildlife management: the use of scientific endangered in the near future throughout knowledge to maintain healthy populations all or a significant portion of its range of wildlife and its habitat and preserve biodiversity Ungulate: hoofed mammal Unguligrade: a foot posture in which an animal walks on its tiptoes, often on hooves

Glossary

98 The Species Question