Bio 312, Spring 2018 Exam 2 ( 1 ) Name: KEY

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1 Bio 312, Spring 2018 Exam 2 ( 1 ) Name: KEY Please write the first letter of your last name in the box; 5 points will be deducted if your name is hard to read or the box does not contain the correct letter. 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 has 100 points total 1. EVLUTINARY CNSTRAINTS. To the right is the cover of the "Monster Manual" published in 1977 as part of the original core rule books for Advanced Dungeons and Dragons, an influential fantasy game. Two of the organisms depicted would never exist in the real world because of some of the evolutionary constraints we discussed in class. For each you will identify which constraint is relevant (i.e., name it) and briefly describe how it relates. Then you will name and describe the remaining two evolutionary constraints. (2 pts ea) (a, 2 pts) Which evolutionary constraint would prevent a dragon, like the one shown, from ever evolving and why? Functional constraint - the surface area of the wings are too small to lift the large body of a dragon of that size. (b, 2 pts) Which evolutionary constraint would prevent a centaur (i.e., the mammal with six limbs holding the club) from ever evolving and why? Developmental constraint - no mammals (or vertebrates for that matter) have ever evolved extra limbs. There seems to be no functional reason why they don't and even rare mutants with extra pairs of limbs aren't seen (rules out pleiotropic and selective). (c, 2 pts) Name and briefly describe a third evolutionary constraint. Selective - selection at one level prevents evolution by selection at another. (d, 2 pts) Name and briefly describe a fourth evolutionary constraint. Pleiotropic - mutations that confer an advantageous trait inevitably have deleterious side-effects.

2 Bio 312, Spring 2018 Exam 2 ( 2 ) Name: KEY 2. TRANSMISSIN GENETICS. Depicted below are a pair of pedigrees (family trees) similar to the one in class, representing males (squares) and females (circles). The left is for a diploid population with the familiar XY sex determination system, and the right is for a haplodiploid population. Males Females Males Females A B C D E F G H Compute the following probabilities below and provide all answers to nearest (2 pts ea) The probability that an autosomal allele in A is also in C due to relatedness. The probability that an allele on an X chromosome in A is also in D due to relatedness. The probability that an allele on an X chromosome in D is also in A due to relatedness. The probability that an allele on an Y chromosome in B is also in D due to relatedness. The probability that a mitochondrial allele in B is also in C due to relatedness. p = _0.125_ p = _0.125_ p = _0.25_ p = _0_ p = _0_ The probability that an autosomal allele in E is also in G due to relatedness. The probability that an autosomal allele in G is also in E due to relatedness. The probability that a mitochondrial allele in E is also in G due to relatedness. p = _0.3025_ p = _0.3025_ p = _1.000_

3 Bio 312, Spring 2018 Exam 2 ( 3 ) Name: KEY 3. HW WE STUDY EVLUTIN. We discussed four basic methods (three in detail) that researchers use when studying evolution. We also provided a series of examples throughout the class that used each of the methods. For each organism and trait described below, name the method of study used (from the three major ones) and what the overall conclusion was. Study organism and trait Vampire bat feeding behavior Method used (1 pt ea) bservation Conclusion (i.e., what did this example illustrate about the evolution of that trait or the evolutionary process as a whole. (2 pts ea) Both kin selection and altruism explained the sharing of blood meals in vampire bats. Testes size in primates. Comparative Polygamous species tended to have larger testes, most likely due to higher rates of sperm competition in polygamous species. Bird tail length and juvenile parasite load Experimental The longer tails indicated a genetic benefit with regard to parasite resistance - indicating that females prefer longer tail due to a "good genes" process. Manatee, sloth, and human cervical vertebrae number Hyena pseudopenises. Comparative bservation The number of cervical vertebrae only seems to evolve in mammals with low metabolisms and low risk of cancer and mutations that influence cervical vertebrae number in humans are associated with increased risk of cancer. This illustrates the likelihood that this evolutionary constraint is a pleiotropic one. Individual level selection seems to be more important than group selection because the pseudopenis evolved because of benefits to individuals despite making the group worse. range, blue, and yellow color morphs in the side-blotched lizard, Uta stansburiana. bservation There appears to be a stable co-existence of these morphs - no single strategy wins. This illustrates that the best strategy can be environment dependent.

4 Bio 312, Spring 2018 Exam 2 ( 4 ) Name: KEY 4. SEMELPARITY AND ITERPARITY. Cole (and Charnov and Schaffer) modeled the factors that influence the likelihood for an evolutionary switch between different types of reproductive strategies; a similar approach can model other types of adaptations. (a, 5 pts) Consider a population of wildtype individuals that reproduce over a number of consecutive years and a mutant that causes individuals to produce twice as many offspring, but they are only 66% as likely to survive to adulthood. By producing more offspring the adults also have a reduced probability of surviving each year. What is the lowest adult survival probability (P m) the mutants could have and experience a fitness value equal or higher than the normal wildtype individuals? Express P m in the form of an equality in terms of b w, C w and P w (assuming some don't cancel out) where these terms represent the values in the wildtype individuals and mutants respectively. Show all the steps in your derivation and express your final answer clearly. Wildtype growth rate: Mutant growth rate: They will have equal fitness when: Which is: From above: This gives: N = (b wc w + P w) N N = (b mc m + P m) N (b mc m + P m) N = (b wc w + P w) N b mc m + P m = b wc w + P w b m = 2b w and C m = (0.66)C w 2b w (0.66)C w + P m = b wc w + P w (1.32) b w C w + P m = b wc w + P w P m = P w - (0.32) b wc w or Pm = Pw - (0.32) bwcw Pm = Pw - (1/3) bwcw (b, 3 pts) Consider a different situation in which a population is declining by 20% per season and adults have a 50% chance of surviving each season. If the juvenile survival rate is 80%, what must the birth rate be? (express this as a decimal number to the nearest 0.001). Show all the steps in your derivation and express your final answer clearly Adult survival P = 0.50 Juvenile survival C = 0.8 For a population to decline by 20% This is when is N = 0.8 N = 0.50 N + b (0.8) N 0.30 N = b (0.8) N 0.30 = b (0.8) 0.30 / 0.8 = b = b B = 0.375

5 Horn size (cm) Horn size (cm) Time oriented Time oriented Bio 312, Spring 2018 Exam 2 ( 5 ) Name: KEY 5. EXPERIMENTAL DESIGN. A fictional organism called a jabberwocky (pictured at right) has large horns growing on its head. Imagine a researcher who is interested in why these horns evolved in this species (some jabberwocky relatives have much smaller horns). The researcher has 2 hypotheses that she will test: (1) The horns are a display trait used in sexual selection. (2) The horns serve as weapons to defend against predators. (a, 4 pts) In order to test the first hypothesis, the researcher shows captive jabberwocky females videos of males with different sized horns (small, medium and large) and measures their orienting behavior (i.e., percentage of time spent facing the video). rienting is previously known to be correlated with mating acceptance. In the space below show a pair of bar charts of hypothetical data from this experiment: n the left, show data that would support the hypothesis. n the right show data that would fail to support the hypothesis. Label the axes clearly with appropriate variables and values. 100% 80% 60% 40% 20% 100% 80% 60% 40% 20% 0% 0% Sml Med Lrg Sml Med Lrg Male horn size Male horn size (b, 4 pts) In order to test the second hypothesis, the researcher measures horn size in 10 related species (values range from 3 cm to 15 cm) where the risk of predation can be estimated on a 0 to 1.0 scale (higher value is more at risk). In the space below show a pair of XY plots of data from this experiment: n the left, show data that would support the hypothesis. n the right show data that would fail to support the hypothesis. Label the axes clearly with appropriate variables and values Predation Risk Predation Risk

6 Reproductive value Bio 312, Spring 2018 Exam 2 ( 6 ) Name: KEY 6. SENESCENCE. Some organisms, such as pine trees and corals, are extremely long lived and experience greatly reduced rates of senescence. - Pine trees reproduce by sending out pollen and fertilizing new seeds in the normal manner. In addition to growing in size, individuals also grow by sending out underground roots that travel a distance and emerge far away and form what appears to be a new tree, but is in fact just an extension of the original individual. - Corals can also live thousands of years, growing larger and showing no signs of senescence the entire time. Corals reproduce by spawning, sending out clouds of gametes into the water, the bigger the coral the bigger the cloud. (a, 4 pts) What shared trait that these two organisms possess causes them to live to be so old, experiencing greatly reduced rates of senescence? Use technical terms from class to propose a hypothesis based on this trait that explains this phenomenon of reduced senescence. The shared trait of these organisms is that their reproduction increases with their age and size. This results in the decline of reproductive value being lessened or eliminated resulting in selection against alleles that are deleterious at old age, the antagonistically pleiotropic ones that cause senescence. I also accepted answers based upon metabolic rate, but those had to explain why these organisms would be expected to have lower metabolic rates. (b, 4 pts) In some populations the reproductive value curves may differ between the genders. In the blank graph below, draw two reproductive value curves, one for males and one for females in a population with two sexes in which the following factors are true: - The population is stable - the overall size remains the same. - Approximately 75% of males and 50% of females die before they start reproducing. - Females start reproducing at approximately 20 years of age and stop after age Males start reproducing at approximately 30 years of age stop after age Age Females Males

7 Bio 312, Spring 2018 Exam 2 ( 7 ) Name: KEY FR THE REMAINING QUESTINS USE YUR SCANTRN FRM, MULTIPLE CHICE: (2 pts each). (1) When some individuals in a species give up reproduction entirely in order to help relatives produce offspirng we refer to this species as being. (A) Altruistic (C) Eusocial (E) Semelparous (B) Asexual (D) Iteroparous (2) Which of the following is the term for when two distinct phenotypes can be produced by the same genotypes depending on environmental cues. (A) Dihybrid cross (C) Phenotypic plasticity (E) Sexual dimorphism (B) Heteromorphism (D) Response activation (3) The Mammalian ear bones develop from which of the following structures? (A) Haeckel's cartilage. (C) Incus. (E) Stapes. (B) Meckel's cartilage. (D) Malleus. (4) ne of the largest difficulties when studying evolutionary psychology is which of the following? (A) Developing more than one hypothesis for the behavior. (B) Distinguishing evolved behaviors from cultural ones. (C) Linking the behavior to a hypothetical fitness advantage. (D) btaining IRB approval for studies with humans. (E) Separating male advantages from female ones. (5) When considering the overall fitness of a gene, the portion that comes from reproduction by relatives is termed fitness. (A) Altruistic (C) Hamiltonian (E) Indirect (B) Direct (D) Inclusive (6) What was the major insight demonstrated by the analysis of the prisoner's dilemma game? (A) Actions that are better for individuals can lead to outcomes worse for the group. (B) Hawks prey on doves because they fly more quickly. (C) Playing aggressively always results in better overall success. (D) Playing conservatively always results in better overall success. (E) When trapped, escape behaviors are more useful than combative ones. (7) Which of the following does NT accurately describe a portion of the logical oops argument for sexual asymmetry leading to differences between males and females? (A) As energy investment decreases, so does the risk of mating with a poor genetic partner. (B) Differences in optimal behaviors can lead to differences in morphology. (C) Males are generally less limited than females in their total number of reproductive events. (D) Males generally contribute less energy than females to each reproduction event. (E) Males generally experience higher levels of intrasexual competition than females. (8) Which of the following was NT a model of female choice discussed in the class? (A) Direct benefit (C) Handicap (E) Territories (B) Good genes (D) Hybridization avoidance

8 Bio 312, Spring 2018 Exam 2 ( 8 ) Name: KEY (9) What is the general term for a mating system where males and/or females can mate with multiple members of the opposite sex. (A) Polyamory (C) Polygamy (E) Polygyny (B) Polyandry (D) Polygeny (10) This species concept focuses on the measurable physical attributes of members. (A) Biological (C) Phenetic (E) Typological (B) Nominalist (D) Phylogenetic (11) This species concept focuses on the abilities of members to interbreed. (A) Biological (C) Phenetic (E) Typological (B) Nominalist (D) Phylogenetic (12) This species concept focuses on identifying monophyletic groups based on DNA sequences or other evidence. (A) Biological (C) Phenetic (E) Typological (B) Nominalist (D) Phylogenetic (13) Physical barriers cause a type of speciation termed speciation if both populations are moderately sized whereas if one is a tiny subpopulation it is termed speciation instead. (A) allopatric... parapatric (C) parapatric... allopatric (E) peripatric... parapatric (B) allopatric... peripatric (D) parapatric... peripatric (14) Which type of selection is predicted to alter the phenotypic mean? (A) Directional (C) Fecundity E) Viability (B) Disruptive (D) Stabilizing The following 3 questions are based upon the videos you watched in preparation for this exam. (15) Which of the following adaptations for mating was depicted? (A) An infectious disease that causes females to lay many more eggs after mating. (B) Broadcast spawning where males release sperm up to 50% of their body mass. (C) Elaborately designed female vaginas that block sperm from reaching the eggs. (D) Flying organisms copulating while in a free-fall towards the ground. (E) Sessile organisms possessing extremely large penises. (16) Which of the following adaptations for mating was depicted? (A) Males carrying sperm on their limbs and using them as intromittent organs. (B) Male competition causing losers to change sex into females. (C) Male deer with antlers so large they cannot fully raise their heads. (D) Males firing darts that contain sperm into females from a distance. (E) Male penises detaching in the females to act as mating plugs. (17) Which of the following adaptations for mating was depicted? (A) Females maintaining harems of up to 20 smaller males. (B) Females pretending to be dead to avoid males attempting to mate with them. (C) Juveniles choosing their sex based on the observed sex ratio. (D) Juvenile males entering females and degenerating physically. (E) Plants that require specific pollinators from a single species to reproduce.

9 Bio 312, Spring 2018 Exam 2 ( 9 ) Name: KEY

10 Bio 312, Spring 2018 Exam 2 ( 10 ) Name: KEY Extra credit: Jokes must be biology, dinosaur, or evolution related for credit 3 points for best joke in class. 2 points for a unique joke. 1 point for a shared joke (2+ students with same or very similar joke). 0 points if not an actual joke/pun.