Evolution in animal diversity

Notes: Although there is a minimum word count of 2,000 words for this exam, you will find that it is likely going to require more than
the minimum to fully answer the question. You may not copy or quote from any source. All information must be re-written in your
own words. Answer all questions. Point value: 100 points. Read the course Style Guide for detailed instructions of structure and
format. Exams must be submitted by the due date and time. Late Exams are NOT accepted without prior approval.

Do not include the question(s) on your essays and exams.
Question 1: Vertebrate Circulatory Patterns (25 points)
Describe the changes in circulation patterns of chordates from the most primitive to the most advanced. Include in your answer:
a. the pattern of flow and function of blood in the Lancelet, Branchiostoma lanceolatum
b. the general circulation pattern of fishes and the special case of fishes with lungs or swim bladders
c. a description of gills and countercurrent exchange for obtaining oxygen
d. the transition in circulation pattern from tadpole to adult frog during metamorphosis
e. the circulatory adaptations of the amniotes: reptiles, birds and mammals

Question 2: From Amniote Egg to Mammals (25 points)
Describe amniote eggs and the transition from animals that lay eggs to placental mammals. Include in your answer:
a. the functions of the amniote egg membranes in the eggs of birds and reptiles
b. the production of bird egg shells at the molecular level and in the reproductive tracts of birds and reptiles,
c. the adaptations seen in the physical fossil record that supports the transition from pre-mammal synapsid egg-layers to
modern, placental mammals that nurse their young. For each adaptation, explain how the fossil record supports the
transition to endothermic homeothermy (warm-bloodedness”).

Question 3: Bird Flight: Mechanics, Weight, Balance and Power (25 points)
Describe flight mechanics and adaptations for flight in birds. Include in your answer:
a. the modern explanation of flight mechanics as described in the text,
b. a description of homeostasis and endothermic homeothermy
c. descriptions of adaptations for flight that reduce weight and those that contribute to balance around the center of gravity,
d. descriptions of mechanisms that increase power (physiological and structural properties, such as food selection, respiratory
refinements, heart rate, mechanical leverage, etc.).

Question 4: Return to Water (25 points)
Describe the adaptations of and challenges to Southern Sea Otters for a return to a life in the sea. Include in your answer:
a. a description of the size, shape, and specialized structures of the Sea Otter body for living in the North Pacific Ocean
b. a description of otter feeding structures and feeding behavior
b. methods by which Sea Otters conserve heat and maintain thermal homeostasis
c. the factors that Sea Otters face as challenges to their survival

References
Immediately following the essay, two lines below the last line of your essay, list all sources used in writing your essay to answer the
question. Do not use in-text citations and do not use footnotes. Simply list your sources in this “References” section. You must have
a References section with at least five references which you have used in preparing your answers: the course textbook, and at least
four additional sources. If you do not include a References section, you will lose 10 points (2 points for each missing source). Be sure
to include the References section with your submission to Turnitin. If you forget, you are able to re-submit until the deadline, but not
after.