EEB 2245W 1st EditionExam # 1 Study GuideSTUDY GUIDE FOR EEB 2245 Exam 11) What type of adaptation would you expect to see in an organism trying to survive in an environment with visual predators?An organism trying to survive in an environment with visual predators will try to protect itself from predators through camouflage, which is the ability of an organism to fool a predator by visually blending itself in the environment. Different organisms change physically to scare the predator away. Some enhance their size to scare the predator by spreading their wings or opening their mouth.2) What’s one possible explanation for powered flight appearing only once in invertebrates and at least three times in vertebrates?Powered flight is a lot more beneficial for invertebrates than vertebrates in their lifestyle. For example, flight helps invertebrates like insects to forage. It has difficult for a honeybee for example to get to the nectar of a flower by climbing up its stem. Vertebrates’ diet however is usually running after another animal or just eating grass.This makes the benefit of flying much less for them.3) Why would it be advantageous for an organism to resemble something else; i.e. a caterpillar that looks like bird droppings or an orchid that smells like carrion?The advantage of that is that they scare the predator away. Specific predators who like specific prey will go after that specific species. Hence, if a caterpillar pretends to be like bird droppings, its predator (who only goes after caterpillars) will not chase it anymore. Similarly, and orchid smells like carrion to not attract the predator. 4) What’s convergence? Can you think of an example we saw in lecture?Convergence, in evolution is where two organisms start developing similar traits in order to survive in similar environments.5) Do similar traits always evolve to solve the same challenges? For instance, are all brightly colored organisms just trying to get a mate?Similar traits don not always evolve to solve the same challenges. In many cases theyare for different purposes. For example, bright colors can be for mating or camouflage or not attracting visual predators. 6) In what ways can humans be a source of selection to other organisms?Human action can cause more danger and change of habitat to many organisms. Thisleads to natural selection where the individuals who survive the best will have their traits passed on to future generations- survival of the fittest.7) What’s the difference between evolutionary change and phenotypic plasticity?Evolutionary change is the change in the genotype (change in allele frequencies) of the populations over time due leading to changes in their phenotype and behavior. Phenotypic plasticity is the change of one organism’s phenotype in order to survive acertain situation or habitat. There are no genotypic changes. 8) Suppose you observe that the average weight of squirrels on campus is greater than their average weight on Horsebarn Hill. Describe how you would use a reciprocal translocation experiment to test the hypothesis that the difference in weight of squirrels on campus and on Horsebarn Hill is the result of an evolutionary change. Explain what outcome(s) would support this hypothesis. What outcome(s) would notsupport the hypothesis? Put both squirrels in a maze and an acorn as the finish prize, and check which squirrel will get to it faster. My hypothesis is that the squirrel who lives on campus is used to the challenge of acorn since it is not as readily available as Horsebarn hill. Hence a plausible outcome is that the campus squirrel will take shorter time to get tothe acorn than the horsebarn hill squirrel. 9) Why do we focus on genetic differences in studying evolutionary change?Genetic differences are important in studying evolutionary change because change inthe genotype (allele frequency) is what results in the evolutionary phenotypic change 10) What is the relationship between Mendelian genetics and population genetics?Population genetic is Mendelian genetic but applied to a population. 11) How can you tell the difference between inbreeding and assortative mating?Inbreeding is the mating of 2 closely related individuals. Assortative mating is choosing of a phenotypically similar mate. 12) What is the most extreme form of inbreeding? Self-fertilization 13) What do you expect the effects of inbreeding would generally be on fitness? Why?Inbreeding would decrease fitness because we are decreasing genetic diversity since similar traits are being passed on to the next generation. 14) Why are inbred lines of model organisms (e.g. Drosophila, mice, C. elegans) often used in biomedical research?They are used to understand human processes without unethically using humans as subjects.15) Under what conditions would assortative mating cause evolution? Under what conditions would it not result in evolution?Assortative mating can cause evolution if the 2 mates are phenotypically similar but genetically not. For example, one has the gene homozygous and the other heterozygous. Assortative mating will not cause evolution if the 2 mates are phenotypically and genetically the same. 13) Given what you know about the different types of non-random mating and their effects on genotype and allele frequencies, what would you expect to be the result of disassortative mating?Disassortative mating will maximize genetic diversity and evolution.Some lecture notes that might be helpful:Activity 1:-Genotype is transmitted, not phenotypeGenes and environment lead to phenotype-Experiment: 1- Reciprocal translocation If genetic information is the same and put in the same environment then the phenotype will be the same for both individuals.2- Common garden: grow both populations in a single environment-Phenotypic plasticity: differences cause because of differences in the environment-Genetics:Mendelian genetics and population genetics which is Mendelian genetics but applied to whole populationsHardy-Weinberg equilibriumGiven certain assumptions:-Allele frequency is constant-One generation in which assumptions are met establishes the equilibrium genotypic frequenciesAfter one generation, no further change Hardy-Weinberg application: testing for equilibrium proportions-The PRNP gene- Prion protein. This gene is highly expressed in the brain-KURU: brain disease epidemic in 1950s-Cannibalism ended and this lead to the last person with prion dying in 2005-Phenyl Ketonuria (PKU)