Biological science asks three major questions of living systems: what, how, and why? What questions involve characterization and categorization. Such compartmentalization is a part of all branches of biology but is a major component of taxonomic research. How questions involve function and mechanism. These investigations are often the purview behavior and physiology. Finally, why questions involve evolution or the changing of things over time. Paleontology and evolutionary biology focus especially on this aspect of life.

The questions addressed in functional morphology (the study of anatomy) are equal parts what, how, and why. More specifically, this branch of biology clarifies: what are the physical (structural) parts of organisms? How do those parts behave? What is the function of various anatomical traits? How and why did these traits change (evolve) over time? Consequently, this laboratory course will ask you to address these issues.

Other components of the lab are for you to examine vertebrates in their native environments, to obtain a short exposure to paleontology, and to learn GPS essentials.

Course Objectives

By the end of this course I expect you to have intelligent answers to the following questions (what, what for or how, and why).

• What are the components (e.g. organs, tissues) of the major anatomical systems for each major vertebrate group?
• What are the functions of these structures? How does the structure implement the function?
• What is the inferred evolution history of each major anatomical system?
• What is a fossil and what can we learn from fossils?
• How does the study of vertebrates in their native environments differ from their study as tissues in a laboratory?

Organization

Because functional morphology is an experimental science we will explore vertebrate anatomy using the scientific method rather than just doing descriptive dissections. Thus we will ask questions, formulate hypotheses, collect measurements, analyze data, and discuss conclusions.

We will use different groups for each exercise to give you a broad exposure to vertebrate anatomy. One exercise for explores fossil vertebrates. For this exercise you will need to go to the Natural History Museum at Amherst College. I also would like you to attend a seminar on Jackal behavioral ecology in April. This course has no final exam, but a practical exam will test your knowledge of vertebrate anatomy towards the end of the semester.

Topical Overview

Here is a brief review of possible laboratory topics:

• Introduction to vertebrates and their anatomy
• Are lamprey sexually dimorphic?
• Do organs scale allometricly with body size in sharks?
• Adaptations for water vs land
• Adaptations for flight in birds
• Neuroanatomy of mammals
• Does diet influence muscle or jaw size in mammals? [the 'jaws' lab]
• Practical Exam
• GPS: understanding space use
• Giving up densities: understanding foraging choices
• Evolution in action: Amherst Museum of Natural History

Assessments

Labs will be assessed with various vehicles and some labs will be assessed in more than one way.

• Worksheets
• Data Sheets
• Data Analysis
• Lab reports
• Oral presentations to the class
• Drawings
• Practical examination

Most work will receive a numerical score but some written material will receive a letter grade . Letter grades will be converted to a point score as follows: A: 10, A-: 9.5; B+: 9, B: 8.5, B-: 8; C+: 7.5, C: 7, C-: 6.5 D+: 6, D: 5, D-: 4 E: 3 incomplete: 0

In-class Assignments

In-class assignments are of three types: worksheets, data sheets, and data analysis sheets. Each of these can be started before class and but will be completed and handed in by the end of lab. Worksheets will ask you to think about general material we will be exploring in labs and will review descriptive aspects of vertebrate anatomy. Data sheets are assigned for those laboratories that focus on hypothesis testing in addition to comparative anatomy. For these you will make measurements and record your measurements on the data sheets. These data will be combined for the whole class and we will work with these data the next week. In that week you will complete a data analysis sheet for the exercise.

Lab Reports and Abstract

When laboratory reports or abstracts are assigned you wil find chapter 3 of Pechenik's 1997 book 'A short guide to writing about biology' useful in directing your writing. Each lab report should include a clever title, an abstract, and an acknowledgements section as well as the usual Introduction, Methods, Results, Conclusions, and Literature Cited. I expect that each report will be 4-6 pages in length of text and include one or two, appropriately annotated, figures (either graphs or tables).

Penalties for Late Work

Any work handed in late (including worksheets, data sheets, data analysis sheets, lab reports, and the abstract) will be penalized 5% per day (24 hr) late up to 5 working days. After that time (1 week) you will receive a zero (0) for the assignment.

Revisions

In order to reward the effort of revision I will allow you to redo one (but only one) assignment for a better grade. To do so you must give me both the revision and the original assignment within one week of the time I return the original work to you. No more than one assignment may be redone, because I do not have the resources to complete the additional grading in a timely fashion. The practical exam can not be redone!

Practical

One week you will be given an opportunity to see how much functional morphology you have learned over the course of the semester. The practical exam will consist of 20-30 stations each with a demonstration or specimen at it and two or more questions about that material for you to answer. You will be allowed 2 minutes per station to answer the questions. You will be expected to know and understand the functions of each structure as described in your Wolff's 'Functional Chordate Anatomy'. Structural, functional, and evolutionary information is 'fair game' for practical exam questions. You should also be able to identify the vertebrates themselves down to common and scientific names for animals you have dissected and to higher taxonomic levels (class or order) for others. You may also be asked about the evolutionary relationships of the major clades of vertebrates.

Amherst Natural History Museum

The Natural History Museum at Amherst College is a small natural history museum with a collection of paleontological specimens on 3 floors. The museum can be reached on the Five-College Shuttle. Before you intend to go, see me to receive the worksheet. Please also sign the guest book at the Museum.

Bring to each lab

Please bring a bound notebook for you to record hypotheses, methods, data, observations, drawings, sources, and any other notes. This notebook will be invaluable to you as you write up your lab reports and should also be helpful in studying for the practical. Use the first two pages for a Table of Contents. So start your note taking on page 3. Use only one side of the page (when you review your notes later you may want to annotate them or add observations on the blank sides). Date each page as you use it.

Safety glasses are required for all dissections. If you have a lab coat or other protective clothing feel free to wear it.

Please also bring this lab manual to class each week.

Miscellaneous

Lab meets Thursday afternoon for three hours. We use Sabin-Reed 205.

Texts (strongly recommended, also on reserve):

Pechenik, JA. 1997. A short guide to writing about biology. Longman, Addison Wesley, NY.

Wolff, RG. 1991. Functional chordate anatomy. Heath Publ, Lexington, MA

Introduction to Vertebrates and Their Anatomy and Origins

Objectives

One objective of this lab is to acquaint you with vertebrates and their relatives in the flesh. A second objective is to have you think about what constitutes the anatomy of a vertebrate. The first objective will be completed through discussion and a notebook exercise. The second objective requires that you complete and hand in a worksheet.

Vertebrates and their Relatives (workbook exercise)

In your notebook draw a Cephalochordate in outline. Add or indicate the 5 derived (synapomorphic) chordate characters. Draw or indicate a synapomorphic trait of cephalochordates. Name a representative cephalochordate (give both common and scientific names). Don't forget that scientific names - genus and species - must be in italics, or underlined if you prefer not to write in italics. Also the generic name is capitalized but the species name is not.

In your notebook draw a Vertebrate in outline. Add or indicate the 5 derived (synapomorphic) chordate characters. Draw or indicate a synapomorphic trait of vertebrates. Name a representative vertebrate (give both common and scientific names).

What is synapomorphic for Urochordates? Name a representative urochordate (give both common and scientific names).

In your notebook make a cladogram for the chordate subphyla.

Tour Sabin-Reed 205. Make a map of the room in your notebook indicating where different vertebrate clades are located. The level of familiarity with the vert lab that this exercise will produce will be helpful when doing the take-home exams and for future laboratories.

An introduction to comparative anatomy (worksheet exercise)

To introduce you to the functional morphology of vertebrates please complete the following self-explanatory worksheet.

Are lamprey sexually dimorphic?

This week we will focus on the anatomy of one of the earliest groups of vertebrates, Petromyzontoidea, the lampreys. You already know quite a bit about lampreys from this week's class exercise. Today you will get to see some of the structures you have been learning about. In your notebook keep a list of things you see today that you had already read or learned about. Later, think about what you didn't observe.

Right now, write in your notebook the Kingdom, Phylum, Subphylum, Class, Order, Family, Genus, and species of lamprey.

Objectives

One objective for this lab was mentioned above: to have you see, in the flesh, the animals you have studied for the past week. A second objective is to have you understand how to quantify simple facts about vertebrate anatomy. In this case, whether or not lamprey are sexually dimorphic in size.

Sexual dimorphism

What exactly do we mean when we say that males are larger than females? How many ways can one measure size? If males are larger, are they larger in all ways? Are all parts larger?

Organization of lab

In this laboratory you will formulate a testable hypothesis regarding sexual dimorphism in lamprey. Then, working in pairs, you will measure a lamprey, dissect it, and weigh or measure particular organs. You may hand in your worksheet as a pair or separately.

The data will be combined for both labs and given back to you next week (week 3) for in-class analysis. A laboratory report from this experiment will be due at the beginning of lab in week 4. Please use chapter 3 of Pechenik's 1997 book 'A short guide to writing about biology' to direct your writing. Each lab report should include a clever title, an abstract, and an acknowledgements section as well as the usual Introduction, Methods, Results, and Conclusions.

Do organs scale uniformly with body size in sharks?

Objectives

One objective of this lab is to show you what the inside of a shark look like. A second objective is to explore the concept of allometry by a quantitative investigation of how different organs within sharks scale with body size.

Allometry

Allometry is about size. About how part of something changes as the whole gets larger or smaller (or different in some other way). Is a particular organ the same percentage of every body. Does it have the same relative size across species? Are brains 5% of body volume in humans? 1% in fish? Do sharks have larger livers than fish? How would you measure this? Is the head of a baby the same percentage of its body as the head of an adult? These are all allometric questions. Today we will explore one of these questions in sharks.

Does a lion have a larger liver than a rat? Does a blue whale have a larger brain than a human? Does a cow have a larger stomach than a cat? Some body parts (for example, hearts or lungs) are probably bigger in bigger animals, whereas other anatomical characteristics (for example, hair length) may not be. Exactly how do we determine how large an organ should be relative to body size?

Organization of lab

The protocol for this laboratory is similar to that for the studying sexual dimorphism in the lamprey. You will formulate a testable hypothesis regarding the scaling of internal organs in sharks. Then, working in pairs, you will measure a shark, dissect it, and weigh or measure particular organs. You may hand in your worksheet as a pair or separately.

The data will be combined for both labs and given back to you next week (week 6) for in-class analysis. A laboratory report from this experiment will be due at the beginning of lab in week 7. Please use chapter 3 of Pechenik's 1997 book 'A short guide to writing about biology' to direct your writing. Each lab report should include a clever title, an abstract, and an acknowledgements section as well as the usual Introduction, Methods, Results, and Conclusions.

Adaptations for Water vs Land

Objectives

One objective of this week's lab is for you to think about how the characteristics of different vertebrate anatomical systems function in different environments. A second objective is for you to study in more detail the anatomy of ectotherms other than lamprey and sharks.

Questions to answer in your notebook (during or after lab)

What traits did the first vertebrates inherit from their aquatic ancestors? How did aquatic vertebrates refine those adaptations for continued life in the water? What changes were made to different systems when vertebrates began to live on land? What refinements resulted from continued life on land?

For each specimen you work with today, write the class, order, family, genus, species and common name in your notebook.

Worksheet assignment

On the worksheet, put the names of 10 anatomical systems next to the letters in the column headed 'anatomical systems'.

Put the common names of the three aquatic and three terrestrial vertebrates you will work on as the appropriate column headings for the table. Aquatic verts in are a, b, and c. Terrestrial verts are d, e, and f.

Now fill in the cells of the table with characteristics of each vertebrate. Circle those characteristics which are adaptations of that anatomical system to the habitat in which that vertebrate lives.

On the reverse of the worksheet, briefly summarize for each anatomical system the major adaptations you observed for life in water and for life on land.

Adaptations for Flight in Birds

Objectives

One objective of this lab is to have you dissect a pigeon so that you can learn how the anatomy of birds is different from that of other vertebrates. A second objective is for you to think about how bird's bodies have adapted to flight and to see what a pervasive affect their mode of locomotion has on their anatomy.

Avian morphology

As we saw last week, for aquatic vertebrates, the characteristics of water, as a substrate, have shaped nearly every anatomical system. In contrast, life for terrestrial vertebrates is dominated by the lack of water, the threat of desiccation. Birds, because they swim through the air, have additional constraints on their anatomy. Some of which are similar to those of fish.

Worksheet assignment

For lab this week you will be using a dissection guide for the pigeon. As you do your work write down each anatomical system on your worksheet. For each system indicate which characteristics are adaptations for life on land (and presumably plesiomorphic) and which characteristics are adaptations for flight (and presumably apomorphic).

In your notebook

Write down why adaptations for life on land observed in birds might be considered primitive. Why would adaptations for flight be considered apomorphic for birds?

Pick two or three birds in the display cases and write down adaptations you see in their feet or bills which you think are apomorphic for that species.

Introductory Neuroanatomy of Mammals

Brains are among the most complex structures that vertebrates possess. As crainiates, vertebrates are defined by the protection given to this integrating piece of their anatomy. This lab focuses on the major anatomical features of vertebrate brains.

Objective

My hope is that in this lab you will obtain a rudimentary understanding of the major anatomical features of mammalian brains.

Procedure

For this laboratory you pin out sheep brains to flag named structures. Each pair will be assigned the letter (S: saggital, V: ventral, L: lateral) that corresponds to a particular view (section) of the brain and to the group of anatomical structures that can be easily observed in that section. You will prepare both a demonstration of your assigned view and a short oral presentation identifying the structures and describing either their functions or their appearance in different vertebrate groups. Use Wolff to obtain information for your short talks. On the reverse of this sheet, for each structure briefly summarize what you told your classmates in your oral presentation.

Note that for the practical exam you will need to know the structures visible in all three sections not just in the one that you pinned out.

Group S:

Sagittal section of sheep brain

Cerebellum, corpus callosum, fornix, fourth ventricle, hypothalamus, medulla, optic chiasm, pineal, pons, spinal cord, telencephalon, thalamus, third ventricle

Group V:

Ventral view of sheep brain

Abducens nerve, Cerebral peduncle, facial nerve, hypoglossal nerve, oculomotor nerve, olfactory bulb, optic chiasm, optic nerve, optic tract, pons, trigeminal nerve, vestibulocochlear nerve (two roots), vagus nerve

Group L:

Lateral view of sheep brain

Caudate nucleus, cerebellum, cerebral cortex (some of which will have to be removed to pin out the other structures), corpus callosum, fornix, hippocampal commissure, hippocampus, lateral ventricle, medulla, olfactory bulb, pons, spinal cord, superior colliculus

Does Diet Influence Muscle or Jaw Size in Mammals?

In this lab, we quantitatively compare the jaw-closing muscles and associated skeletal structures of an herbivore (a sheep, Ovis aries) and a carnivore (a mink, Mustela vison). Sheep are much larger than mink, so differences in the absolute size of muscles and bones may not be due just to diet. To compensate for this we will have to calculate and compare the percentage of each muscle relative to the total jaw-closing muscle-weight. In addition, our measurements of the length and width of various skull and mandible dimensions will have to be compared relative to greatest length or width. Worksheet.

The data will be combined for both labs and given back the week after the practical exam (week 12) for in-class analysis. An abstract from this experiment will be due at the beginning of lab in week 13.

Muscles of mink which elevate the mandible

Muscle Origin (on skull) Insertion (on mandible)

Temporalis Temporal fossa Coronoid process

Masseter Zygomatic arch Masseteric fossa

Pterygoid Skull behind last Medial mandible

• Molar & pterygoid fossa

Muscles of sheep which elevate the mandible

Muscle Origin (on skull) Insertion (on mandible)

Temporalis Temporal fossa & crests Coronoid process

Masseter Zygomatic arch & Angle of ramus

• Lateral surface of
• Facial crest

Pterygoid Pterygo-palatine fossa Concave medial surface of ramus

Skull Measurements

Greatest length of skull - From the most anterior part of the rostrum (excluding teeth) to the most posterior point of the skull

Zygomatic width - Greatest distance between the outer margins of the zygomatic arches

Palatal length - From anterior edge of premaxillae to anteriormost point on posterior margin of palate

Mandible (ramus) Measurements

Greatest length - Greatest length of the mandible excluding teeth

Greatest width - Width from tip of coronoid to tip of angular process

Condyle to angle - Length from condyle to tip of angular process

Condyle to coronoid - Length from condyle to tip of coronoid process