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Bio 312, Fall 2016 Exam 1 ( 1 ) Name:______

Please write the first letter of your last name in the box Written answers should be concise and precise; answers typically have short correct answers. Regrade requests cannot be made for exams completed in pencil for any reason. The exam is worth 100 points total

(1) THE LYSTROSAURUS WORLD

Today humans are one of the dominant on the planet; there are over 7 billion of us. Even when we consider chickens (approx. 19 billion), cows (approx. 1.5 billion), and pigs (approx. 1 billion) (www.fastcoexist.com/3031945), the number of Homo sapiens individuals represents a major proportion of the terrestrial population. The world has not always been this varied or dominated by humans however - at the end of the Permian a mass event killed almost all on Earth. indicate that at the beginning of the Triassic approximately 95% of all terrestrial vertebrates were members of the same genus. Although individuals ranged in size from quite small to as large as modern humans, most vertebrate life walking on Earth belonged to only 4-6 species within that genus ... Lystrosaurus.

(a, 2 pts) Approximately how long ago did Lystrosaurus dominate the planet? ______MYA

This example perfectly illustrates one of the lines of evidence that I described fossils as providing - namely, that extinct species indicate change in living organisms over long periods of time due to their absence today. In the discussion of fossils I also discussed two other pieces of information that support an evolutionary model for the we see in the world today. Describe each of these, including both the observation and the logic of the support.

(b, 4 pts) The second aspect of fossils that support the evolutional theory of life is ...

(c, 4 pts) The third aspect of fossils that support the evolutional theory of life is ...

Bio 312, Fall 2016 Exam 1 ( 2 ) Name:______

(2) GEOLOGIC RECORD. Uranium to Lead decay, 235U to 207Pb, is often used to date the ages of very old rock formations. When zircon forms it incorporates Uranium, but not lead, so we can assume that the initial crystals of zircon have no lead. The half-life of the 235U to 207Pb decay process is 710 million years.

(a, 3 pts) If the ratio of Uranium-235 atoms ______Million years old to Lead-207 atoms in a zircon crystal is 1:15, how old is the crystal?

There is a second type of radioactive decay, 238U to 206Pb, which has a half-life of 4.47 billion years. Since natural Uranium is a mix of both isotopes, in actual studies of uranium to lead decay both types of Uranium and both types of lead must be estimated separately in order to get accurate results.

(b, 3 pts) If we assume that all the Uranium in a crystal is Uranium-235 and that all the Lead in the crystal is Lead-207, but there is also Uranium-238 in the original sample, would the estimated age we obtain from comparing the overall Uranium to Lead ratios be too ancient or too recent? Explain your reasoning.

(3) COMPOUND INTEREST. Imagine that you have a loan with an initial balance of $1,000 and you make no payments for a given amount of time. You will calculate the new balance after this period of time for the following two situations. Provide your answers to the nearest dollar.

(a, 2 pts) If the loan carries an annual interest rate $ ______of 10%and you wait 5 years, what is the new balance?

(b, 2 pts) If the loan carries an annual interest rate $ ______of 5%and you wait 10 years, what is the new balance?

(4) ARTIFICIAL SELECTION. Consider the data set to the 15 20 22 25 right showing the mass at 6 weeks measurements for a set of 20 mice. You may assume that this trait is known from 17 20 23 25 previous experiments to have a narrow heritability of h2=0.7. Imagine that we divided these mice into two equal 18 21 24 27 groups based on their size (i.e., one group is the biggest half, 18 21 24 27 the other are the smallest mice) and then randomly mated them within each group. 19 21 25 28

(a, 4 pts) Based on this data, what would you expect the mean mass at 6 weeks to be for the Mean mass = ______offspring arising from the smallest group?

(b, 4 pts) Based on this data, what would you expect the mean mass at 6 weeks to be for the Mean mass = ______offspring arising from the largest group? Bio 312, Fall 2016 Exam 1 ( 3 ) Name:______

(5) CROSSWORD PUZZLE. FILL IN THE BLANKS (1 pt. per correct answer).

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ACROSS

3 Invented the concept of scala naturae. 7 The three eras within the eon are the Paleozoic, Mesozoic, and the _____ . 10 Mammalian group that gives live birth to extremely underdeveloped young and keeps them in pouches for maturation. 11 Used sophisticated mathematical tools to model the probability of fixation of novel alleles and the time that requires. 13 Most ancient period in the Mesozoic. 15 Phylum described as "segmented worms" which includes leeches. 16 group including T. rex and modern birds. 17 Explained apparent geologic change via a model of . 18 Most recent period in the Paleozoic. 19 Eon before life began.

DOWN

1 Fisher, Wright, and ___ are credited with the modern synthesis of and . 2 One of the two epochs within the quaternary period. 4 Mammalian order that aardvarks belong to. 5 Phylum including mushrooms and yeast. 6 Birds first evolved during this period. 8 Mammalian order that dogs belong to. 9 Co-discovered of the theory of evolution by . 11 Published the laws of planetary motion. 12 Order encompassing frogs and toads. 14 Mammalian order that whales belong to. Bio 312, Fall 2016 Exam 1 ( 4 ) Name:______

(6) PHYLOGNETIC RELATIONSHIPS.

(a, 4 pts ea) In the boxes below provide the phylogenies for the following sets of taxa:

Amphibians Cats Birds Dogs Insects Echidna Mammals Hippos Segmented worms Kangaroos Sponges Whales

(b, 3 pts) In the box below and to the left draw a phylogeny (with the base of the tree on the left and terminal taxa on the right) that is described by this set of statements: ► The group consisting of RED, PURPLE, and GREEN is monophyletic. ► Taxa BLUE and ORANGE are sister taxa. ► RED is basal to taxa PURPLE and GREEN ► Taxon YELLOW is the outgroup to all the others.

(c, 3 pts) In the box below and to the right draw a phylogeny that represents the same history, but has a different order of taxa names when looked at from top to bottom.

Bio 312, Fall 2016 Exam 1 ( 5 ) Name:______

(7) ESSAY ABOUT THE EVOLUTION OF Biston betularia carbonaria and typica. In the lectures this species was used to illustrate one of the lines of evidence for evolution. You will describe this example in your own words below. Be sure to describe the following 5 things: the species in question, the variant trait that evolved, the relevant environmental conditions and selective pressure involved, the full course of the evolutionary changes that took place, and how this supports the evolutionary explanation for the modern state of biodiversity on Earth. You must also include one relevant quantitative figure and make reference to it in your description. (10 pts)

Bio 312, Fall 2016 Exam 1 ( 6 ) Name:______

FOR THE REMAINING QUESTIONS USE YOUR SCANTRON FORM, ► MULTIPLE CHOICE: (2 pts each).

(1) Which of the following is NOT one of the biodiversity-defined geographic regions described in class? (A) Nearctic (C) Palearctic (E) Ethiopean (B) Neotropical (D) Paleotropical

(2) According to the you were given (i.e., do not consider any taxa that may have been omitted), which of the following statements is false? (A) Amphibians are monophyletic. (D) Mammals are paraphyletic. (B) Birds are monophyletic. (E) Reptiles are paraphyletic. (C) Fish are paraphyletic.

Use the four phylogenetic trees shown here for the next three questions. The shade of the circles for each extant taxon indicates the morphology of the trait in question and you can assume that the outgroup trait represents the ancestral state.

(3) Assuming that both types of changes (dark to light and light to dark) are possible, what is the minimum number of evolutionary changes that would have to have happened if the phylogeny on the left is correct? (A) 1 (B) 2 (C) 3 (D) 4 (E) 5

(4) Assuming that both types of changes (dark to light and light to dark) are possible and considering the phylogenies from left to right, what is the minimum number of evolutionary changes that would have to have happened for each phylogeny? (A) 2, 3, 4, 4 (C) 4, 4, 4, 5 (E) 4, 5, 5, 5 (B) 3, 4, 4, 4 (D) 4, 4, 5, 5

(5) Assuming that only changes from light to dark are possible and considering the phylogenies from left to right, what is the minimum number of evolutionary changes that would have to have happened for each phylogeny? (A) 2, 3, 4, 4 (C) 4, 4, 4, 5 (E) 4, 5, 5, 5 (B) 3, 4, 4, 4 (D) 4, 4, 5, 5 Bio 312, Fall 2016 Exam 1 ( 7 ) Name:______

(6) Which of the following taxa is NOT an Eon? (A) Archean (C) Paleozoic (E) Proterozoic (B) Hadean (D) Phanerozoic

(7) Which of the following is NOT a member of ? (A) Anemone (C) (E) Starfish (B) Earthworm (D) Lamprey

(8) Which of the following is NOT a ? (A) Amphioxus (C) Hagfish (E) Starfish (B) Eagle (D) Horse

(9) Which of the following is closest to when life on Earth began? (A) 200 million years ago (C) 800 million years ago (E) 3200 million years ago (B) 400 million years ago (D) 1600 million years ago

(10) Which of the following taxa is most closely related to rodentia? (A) Carnivora (C) Primates (E) Xenartha (B) Cetacea (D) Proboscidea

(11) Ducks do not belong in which of the following taxonomic categories? (A) Amniota (C) Craniata (E) Synapsida (B) Chordata (D) Diapsida

The following 3 questions are about the video you were required to watch for this exam.

(12) Which of the following occurs toward the end of the episode? (A) The host describes how antibiotic resistance is due to bacterial evolution. (B) The host describes the structure of the egg in different reptilian and bird taxa. (C) The host visits a professor at Harvard to talk about Polar Bear Evolution. (D) The host visits a fictional building called the "Halls of Extinction." (E) The host visits the Galapagos to show where Darwin saw iguanas.

(13) Using cartoons, the episode examines natural selection in which of the following taxa? (A) Brown and white bears. (D) Striped and spotted (B) Endothermic and ectothermic snakes. (E) Tall and short pea plants. (C) Slow and fast tuna fish.

(14) In the description of the evolution of the , the narrator makes a point about why our are not as good as they could be. What point was this? (A) Compound eyes evolved first and eyes came later and are therefore compromised in quality. (B) Eyes initially evolved in short-lived organisms so now lenses degrade in longer lived organisms like humans. (C) Eyes initially evolved to see in water and out of water the images are now somewhat distorted. (D) Eyes initially evolved with blind spots to protect them from intense light gradients, but now this blind spot serves no purpose. (E) Eyes initially evolved using a that is only sensitive to of light more common millions of years ago and less common now, leading to poorer modern vision.