# Evolutionary Genetics 02

 What is Fisher's Theorem of Natural Selection? The rate of increase in fitness of any organism at any time is equal to its genetic variance in fitness at that time. What is the equation for Fisher's Theorem? dr / dt = sigma squaredwhere r = intrinsic rate of growth What is absolute fitness denoted by? W What is relative fitness denoted by? w How is relative fitness calculated? divide all absolute fitnesses by the highest oneone value always equals 1.0, and the rest are less than that How is absolute fitness calculated? observed number with given genotype in one generation divided by observed number of that genotype in previous generation Fitness is a prediction based on observations; not _______. survival The fittest _____________ survive, and the survivor is __________. does not necessarily survive; not necessarily the fittest What is the marginal fitness? wA or wathe sum of relative fitnesses of genotypes containing the allele in question weighted for their respective frequencieswA = pwAA + qwAawa = pwAa + qwaa Always calculate p as ___________ not as p^2. Why? (nAA + nAa/2)/N only use p^2 if it's in HW equilibria Selection can act on _________________, ___________, ____________, and __________________. the level of formation of mating pairs (sexual selection), fertility (ability to produce functional gametes), fecundity (reproductive success of mating pairs), and viability (survival to adulthood) What is viability? survival to reproductive age What is fecundity? actual reproductive output in numbers What is fertility? ability to reproduce, make gametes What is the equation for fitness? What do the variables mean? w = 1 - sw is the fitness coefficients is the selection coefficientw is the proportion that survive to reproduces is the proportion that die What does it mean if all three relative fitnesses = 1? The population is in HW equilibria What are some characteristics of selection against a completely dominant condition (if p is high)? AA and Aa are equally selected againstaa has so few numbers that even though they produce more offspring, it takes a long time for them to outnumber AA and Aafixation of the recessive allele takes place in a realistic timeframethe lower w is relative to 1.0, the more rapid the fixation of aa What are some characteristics of selection against a completely recessive condition (if p is low)? p rises rapidlyeven under strong selection, recessive allele persists for MANY generations because it hides in the heterozygotesof all genotypes containing a, q/(1-p) is proportion of homozygotes, 2p/(1+p) is proportion of heterozygotesthe lower w is realtive to 1.0, the more rapid the change in p How do you calculate mean fitness? p^2wAA + 2pqwAa + q^2waa What does it mean if mean fitness (w line hat) adds up to less than 1? selection is present AuthorMiskozi ID79254 Card SetEvolutionary Genetics 02 Descriptionevolution Updated2011-04-13T02:59:16Z Show Answers