ZOOL 4133 1nd EditionExam # 2 Study Guide Lectures: 9 - 16Lecture 9-11 (February 12 - 19)Quantitative Genetics, Sexual Selection, Social Behavior, Life History, Aging and Life HistoryWhat are traits controlled by? What are most traits determined by?-Multiple loci control most traits and the combined influence of “multi-locus genotypes and the environment are what most traits are determined by.What are quantitative genetics used for?- Connecting genotype to phenotype, predicting responses to selection, measuring heritability and the strength of selection.Review the Punnett squares in the notes for examples of determining F1 and F2 genotypes and phenotypes. What happens to the distribution of traits as more loci are added?- Offspring become more heterozygous and less homozygousWhat is the purpose of measuring heritable variation?- Heritable variation is necessary for evolution to occur (review Darwin’s four postulates). It also allows for the prediction of responses to selection.o This can assist with selecting for desirable traits in artificial selection.What is the heritability range?- 0-1What is the definition of broad-sense heritability? What is the equation for broad-sense heritability and what do the variables stand for?- Broad-sense heritability is the “fraction of the total variation in a trait that is due to genetic variation”. The equation is as followso Heritability = (Vg/Vp) OR heritability = Vg(Vg+Ve)- Vp – “total phenotypic variance in a trait”- Ve – “variation in a trait due to environmental variance”- Vg – “variation in a trait due to genetic variance”What is the definition of narrow-sense heritability (h2)? What is the equation?- “the fraction of the total variation in a trait that is due to additive genetic variance.”- Equation is as follows:oh2 = Va/Vp = Va/(Va+Vd+Ve)oVg=Va+Vd- Subscripts on the variables are the same as broad-senseWhat is selection differential equal to?- Selection differential is equal to the difference between the selected individuals mean andthe mean of the total populationWhat is the equation for predicting a response to selection? What do the variables stand for?- R=h2S-h2- heritability-S− selection-R− per-generation responseDefine Direction selection, stabilizing selection and disruptive selection.- Directional selection is the consistent increasing or decreasing of fitness with the value of a trait – the highest or lowest fitness are seen in individuals with the extreme values of the trait. Stabilizing selection occurs when the highest fitness is seen in individuals with intermediate value of the trait. Disruptive selection occurs when the individuals seen with the extreme trait values have the highest fitness. What is the definition of adaptation?- “a trait, or integrated suite of traits, that increases fitness”What could be the significance of the adaptation of zebra stripes (4 alternative hypotheses)?i. Avoiding predationii. Managing heatiii. Protection from fly bitesiv. Concealment (camouflage)b. These need to be testedWhat are the four important things to remember about adaptation?a. Not every trait shown by an organism is an adaptive oneb. Not every adaptation is flawlessc. The origin of a trait is not always represented or reflected in its current usaged. Differences seen in populations are not always adaptationsWhat are the trade-offs and constraints of adaptation?a. Selection can only influence and act upon existing variationsb. Genetic correlation results in genetic constraintc. “developmental programs impose constraints”d. Body plans are constrained by physics and environmentse. Trade-offsi. Resources may be taken from one aspect of a phenotype in order to provide for another. Lecture 12-14 (February 26- March 03)What is sexual selection and what does it require?- The ability to obtain mates varies, which results in differential reproduction. It requires heritable variation- in regards to characteristics that affect reproductive successWhat is sexual selection able to select for? Are there any costs?- Sexual selection is able to select for characteristics which increase the reproductive success of an organism. This is at the expense of survival and is also in contrast to natural selectionWhat are the differences between the reproductive investments of males and females?- Males : small gametes, limitless amounts of sperm, can increase fitness with multiple mates. Limiting factor is the ability to attract females.- Females: large gametes, can be choosy, finite number of eggs, only need one mate to reach maximum reproductive output. Limiting factor is time and resources available for offspring. What is the Bateman gradient? Is this always the case?- The theory that reproductive success/variance is greater in males than females. Females must invest more energy into producing offspring. This is not always true. The sex that has to invest more is the choosier sex – sometimes this applies to males.What are the differences between intrasexual and intersexual mating strategies?- Within the sex : Various mating strategies, after-mating competition such as sperm competition, infanticide, territorial fighting, ritual fighting, and defending of resources- Between : elaborate shows/displays, intricate phenotypesWhat happens when females are the choosier sex?- When females show preference for particular male display traits, they drive the evolution and development of sexually-selected traits. This can lead to runaway selection where the male traits become extraordinarily elaborate. What are females choosing for when they show preference for certain male traits?- When females choose larger, or more colorful traits, they are choosing the “healthier” male. Males that have more elaborate traits are advertising that they have the energy to spend on developing those traits. These healthy genes can be passed to their offspring. What are the four main types of social behavior? What do each of these mean?- “mutual benefit, Selfishness, Altruism, Spite”o Mutual: fitness of actor and recipient are both increasedo Selfishness: actor benefits while recipient loseso Altruism: recipient benefits at expense of actoro Spite: all loseLecture 15-16 (March 5- 10)What is the difference between direct and indirect fitness?- Direct fitness occurs when genes are contributed to the next generation by an individual’s direct reproduction. Indirect fitness occurs when genes for the next generation are