BIO220 MIDTERM EXAM QUESTIONS WITH VERIFIED SOLUTIONS

Fst=1 complete differentiation Fst=0 no differentiation Brainpower Read More Previous Play Next Rewind 10 seconds Move forward 10 seconds Unmute 0:00 / 0:00 Full screen Patrilocality the Females move and Males stay (lower Y variation, higher mDNA variation) Matrilocality the Males move and Females stay (higher Y variation, lower mDNA variation) mitochondrial DNA inherited maternally Y chromosome inherited paternally Beneficial mutation a mutation that enhances an organism's fitness. More replacement mutations than synonymous Neutral Mutation a mutation that has no effect on survival or reproduction. Similar quantity of replacement and synonymous mutations. Deleterious mutation mutations that are harmful to an organism. more replacement mutations than synonymous. dN/dS > 1 beneficial. substitution rate for replacement exceeds synonymous. dN/dS < 1 deleterious. substitution rate for synonymous exceeds replacement. dN/dS = 1 Neutral. equal rates of substitution for both. genetic hitchhiking the process by which an allele is able to "ride along" with a nearby favorable allele to which it is physically linked and thus increase in frequency Homozygous Having two identical alleles for a particular gene cultural impact cultural practices lead to selection on both humans and agricultural partners. (seen in starch digestion, lactose tolerance, etc.) coevolution Process by which two species evolve in response to changes in each other sexual coevolution two sexes impose selection on each other agricultural coevolution humans and their agricultural species impose selection on each other rice, maize, wheat 3 species that account for 60% of food energy crop diversity bottleneck only a small subset of species of the wild type are selected to harvest; there is less diversity in the crop than the ancestors. Genetic variation in crops consequence of domestication. H average frequency of heterozygous individuals per teen locus P proportion of gene loci that are polymorphic Pi average number of nucleotide differences per site (for any randomly sampled pair of nucleotides) polymorphism the existence of two or more forms of individuals within the same animal species (independent of sex differences) why do we care about genetic variation in crops? 1. clues to artificial selection don't in the past 2. pest and pathogen management 3. future improvement of crops N (census size) total number of adults in population Ne (effective size) the size of an idealized population [all individuals with equal opportunity to pass on their genes] Ne<<N more important for evolutionary analysis Irish Potato Famine The potato crops in Ireland became diseased and the Irish starved. Set off the immigration to the U.S. it was the same variety so they all died clonal propagation asexual reproduction. no genetic variation (which allows some survivors) no opportunity to improve resistance through natural selection. genetic effects of declining populations genetic drift is enhanced inbreeding genetic drift variation in the frequency of a gene allee effects Growth rate decreases as population density decreases genetically depauperate very very low variation/diversity within the species Extinction Vortex A downward population spiral in which inbreeding and genetic drift combine to cause a small population to shrink and, unless the spiral is reversed, become extinct. Florida panthers case study getting hit my vehicles (demographic) was reducing population rapidly. developmental abnormalities were arising(suggesting inbreeding depression) transplanting a few new individuals rescued the population but it fell to the same trend due to demographic problems Scandinavian wolves transplanting an individual animal can solve inbreeding in the SHORT TERM general rule of harvesting harvest out recruitment and leave the stock alone dN/dt change in abundance over time r intrinsic rate of population growth K carrying capacity model for how populations grow dN/dt = rN[(K-N)/K] ideal harvesting strategy harvest K/2 individuals per year (to maximize population growth rate) Maximum Economic Yield (MEY) where benefit-cost is maximized profit maximized Maximum Sustained Yield (MSY) point of max population growth yield maximized harvesting pressures - financial pressure to continue harvesting - demand for food