EnSt/Bio 295 Exam I(FL08) This test is worth 100 points; you have approximately 50 minutes. Allocate your time accordingly.

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1 EnSt/Bio 295 Exam I(FL08) This test is worth 100 points; you have approximately 50 minutes. Allocate your time accordingly. MULTIPLE CHOICE (2 points each) A_ 1. Which of the following are adaptations? a) Modifications to the penguin wing to make them better swimmers b) Any trait which increases survival for an organism in its current environment (aptation) c) the preseance of wings in the penguin for swimming (exaptation) d) a and b a) all of the above B_ 2. Evidence for evolution comes from a biogeographical analysis of species diversity patterns of the Galápagos (Darwin s finches being an example). Which of the following are true for this example? a) The finches had dispersed from south-east Asia and adapted by natural selection to resemble South American species, who share a similar environment. b) The finches shared a common ancestor with the South American finches, as opposed to having been specifically created for the Galápagos archipelago. c) The similarity between these species and the species of the Cape Verde Islands off the coast of Africa (an island of similar topography) indicates common ancestry for both. d) All of the above are plausible theories e) None of the above E 3. Reinforcement may accompany speciation when the following process occurs: a) Secondary contact following divergence in allopatry b) Dissassortative mating (preferentially mating with individuals unlike yourself) c) Hybrid inferiority (reduced hybrid fitness) d) All of the above e) a and c D 4. A metapopulation structure complicates conservation because a) Each subpopulation is locally adapted b) Extinction is inevitable for the metapopulation c) Species with metapopulation structure cover larger ranges d) Both patches and dispersal routes must be conserved e) Metapopulations always have low growth rates E_ 5. Identify which event would not be classified as allopatric speciation: a) Finches colonize an archipelago of islands in the pacific and speciate from their mainland cousins. b) The Andes mountain range uplifts, dividing the range of a lowland frog species that proceeds to speciate into western and eastern forms. c) Two populations of snails are located so far apart that they are never able to mate or make contact with one another. d) A river divides a population of terrestrial lizards which speciate into two forms at the riverine barrier. e) None of the above. (All are allopatric) For the following question, assume the following: A species can withstand a narrow range of temperature. Above 100 F there are no species present. In the range from 97 F 100 F and 90 F 94 F there are a few individuals present. Below 90 F there are no individuals present. B_ 6) What would you label the range of temperature from 90 F to 94 F for this particular species? a) zone of intolerance b) zone of physiological stress c) tolerance limit range

2 d) optimal range e) range of tolerance A 7. Darwin s theory of evolution was original because a) he proposed a mechanism for evolutionary change that worked b) he provided a working theory of inheritance c) It was based on observations from the natural world. d) He introduced the world to the concept of evolution e) All of the above B_ 8) Different species who are biologically capable of mating and producing offspring but do not because they have different habitat preferences are separated by a) post-mating isolation b) ecological isolation c) behavioral isolation d) mechanical isolation e) a and b 2) True-False (2 pts each) F a. The Modern Synthesis view of biological inheritance results in a blending of variation, washing out unique traits. Modern synthesis corrected the mistake that was the blending theory of inheritance. F b. Genic selection is the fundamental unit of selection. It is individual selection. F c. Pre-mating isolation mechanisms are required for both allopatric and sympatric speciation. Post-mating isolation mechanisms can lead to isolation in allopatry F d. When an animal is placed in a new environment, it increases the chances that a new mutation will occur to make them better adapted. Beneficial mutations will be favored by selection but not more likely to occur. F e. The fact that humans have increased some species ranges is a good thing and provides evidence that conservation is working. Removal of competitors and introduction of invasives leads to expanding ranges. T f. Stabilizing selection often results from the notion of trade-offs and is the most common type found in nature. F g. The only reason Darwin s theory of evolution by natural selection was not widely accepted at first was because it went against the pre-existing views on the world and religion of his time. He didn t get everything correct. T h. Group selection may often help to push the evolution of favorable traits at the individual level along but would only be able to counteract the force of individual selection in the most extreme examples. F i. The evolution of horses provides an excellent example of the directional nature of natural selection. Evolution by natural selection is not directional.

3 F j. The Northern Elephant Seal population has rebounded to healthy numbers after being hunted to near extinction in the late 1800 s. However, because the founders of today s population only contained a subset of the pre-existing variation, the northern elephant seal now has very little genetic variation despite large population sizes to a process called the founder effect. This is the bottleneck effect. Fill in the blank. Be as specific as possible. (2 points each) 1) Name the three main tenets (or requirements) in Darwin s theory of evolution. (complete sentences not needed). (4 pts total, 2 for each of the last 2) (1) Variation (2) Heritability (3) Differential Survival and Reproduction 2) Fecundity is a term used to describe the potential reproduction of an individual whereas fertility refers to the actual or observed reproduction. Use alternative terminology (not hypotheses) for adaptation in the following two questions. 3) Mammalian male nipples are an example of a(n) non-aptation. 4) Human fingers are used for typing on a computer keyboard and are thus considered a(n) exaptation for typing. 5) Antagonistic interactions between individuals lead to uniform/regular dispersion patterns, whereas neutral interactions lead to random dispersions. 6) The rate or speed of evolution is said to be a continuum between gradualism and punctuated equilibrium. 7) The wing of a bat, front flipper of a dolphin, and arm of a human are an example of homologous structures. 8) The key component for defining species under the Biological Species Concept is that the two potential species must be reproductively isolated. Short Answer 1) In the African seed-cracker that we discussed in class, disruptive selection has led to two different beak types (large and small). If disruptive selection is an important force for speciation, why hasn t the seed-cracker speciated? (2 You should only need a sentence or two. No reduced hybrid fitness with Dom/rec inheritance model of beaks.

4 2) A change in an organism s physiology in response to environmental change is sometimes mistaken for adaptation. What is this process called and in one sentence, what is a requirement of evolution that explains why this is not considered an adaptation? (2 Acclimation genetic change between generations, there is no genetic change in acclimation 3) In class, I read an article that claimed we could have a class action lawsuit against our maker. What is meant by this and how is it relevant to the evolution/intelligent design debate? (4 Class action lawsuit refers to the idea that while we are complex organisms, we are far from perfect and are littered with imperfections (they don t have to use these exact words but must refer to the idea of imperfections or mistakes in design). (2 It is relevant as a counter to the intelligent design argument. This imperfect design, artifacts of evolution, is not what you would expect from a supreme creator but instead shows evidence of our evolutionary past. (again, do not need exact words just an understanding of how this applies to the debate.) 2 points 4) A) What is meant by the idea that Natural Selection favors relative not absolute values of traits? Use an example if it helps. B) How does this idea help to expain the evolution of a complex trait such as an eye? (6 a) Traits are not favored because of some threshold value, like over 20mph is good, under 20 mph is bad. Traits are only good or bad in the eyes of selection as they relate to the other traits present in the population. They are favored if they are better than the other options. b) Complex traits to not need to evolve in one perfect step. They evolve with small changes that only must give some benefit relative to others without the trait.

5 5) List three advantages each for group behavior with respect to both predator avoidance and foraging. (6 Predation Foraging 1) Group Defense Information transfer 2) Alarm calls Higher efficiency catching same prey 3) Dilution Effect Ability to catch new prey 4) Increased vigilance 6) What is the key to long term stability for a metapopulation? Explain why maintaining all existing populations but as a smaller size might be problematic to this stability. (6 Balance between extinction and recolonization of subpopulations Smaller sized subpops leads to higher extinction rates and lower immigration/dispersal/recolonization rates. This could throw the balance off from both directions. 7) Briefly describe the concepts of ecological traps and pseudo-sinks. Describe an example for each to support your explanation. (8 Ecological traps - areas whose conditions appear favorable to the organism but are in fact unsuitable for long-term population maintenance for reasons that the organism is unable to recognize. Ex. Agricultural fields - appear to be great habitats to many ground nesting birds and small mammals but the heavy use of fertilizers, pesticides, and frequent plowing actually make them death traps for young inds. Pseudo-sink - a source masquerading as a sink - ex. Checkerspot butterfly - Migration rates are higher moving from Clear-cuts to rocky outcrops and population densities are smaller on outcrops with densities declining as you move away from the clear-cut. Clear-cut looks like the source population but its actually movement to a more desirable and long-term food source. Rocky outcrops are the source. Without them the population would disappear.

6 8) What is an environmental indicator species? Give two examples from class. (4 EI A species that is particularly sensitive to specific environmental conditions and can therefore be used as an indicator of habitat quality or environmental trouble. Any example from class is fine, i.e. white pines and air pollution; trout and welloxygenated streams; spotted owl and old growth forest; etc. 9) Briefly explain three idea other than constraint that could lead to non-adaptive traits in a population. A couple sentences each is enough. (9 Any of the following are ok but you must explain how it leads to a non-adaptive trait. a) Gene flow genes may be from neighboring population adapted to different environmental conditions b) Genetic drift Drift can increase the frequency or lead to fixation of nonadaptive traits c) Functional equivalence difference between traits is not adaptive hust different solutions to the same problem d) Founder effect or bottleneck increases frequency of rare, recessive traits\ e) Vestigial structures holdovers from previous design may no longer be adaptive f) Genetic linkage Adaptive trait may be linked to non-adaptive trait. Pair will be passed on as long as the net effect is positive. g) Pleiotropy gene affects more than one trait again as long as net effect is positive, gene will be favored even if some affects are non-adaptive h) Trade-offs Some traits are required to perform multiple functions which makes them unable to be optimally adaptive for any one, Ex-amphibian limbs