UCSB EEMB 2 Final Exam Exam full solution packxam Questions and Answers 2024

UCSB EEMB 2 Final Exam adaptative radiation - diversification of a group of organisms into forms filling different ecological niches allopatric speciation - aka geographical isolation: biological pops of the same species become isolated from each other to an extent that prevents or interferes with gene flow allopolyploidy - individual or strain whose chromosomes are composed of more than two genomes each of which has been derived more or less complete but possibly modified from one of two or more species -mating of diff species analogous traits - similarity due to convergent evolution, not common ancestry anisogamy - sexual reproduction by the fusion of dissimilar gametes -smaller gamete usually male autopolyploidy - polyploidy in which the chromosome complement consists of more than two copies of homologous chromosomes background extinction rate - aka normal extinction rate, the standard rte of extinction in earth's geological and biological history before humans became a primary contributor to extinctions balancing selection - multiple alleles are maintained in the gene pool of a population at frequencies higher than expected from genetic drift alone -could be due to heterozygote advantage, coevolutionary dynamics (other species exhibits a common trait in first species), negative assort mating, spatially (temporally fluctuating selection) -leads to negative frequency - dependent selection: allele more common decreases fitness biological species concept - explanation for how species form. Species = pop of orgs that can breed to produce fertile offspring clade - group of organisms evolved from a common ancestor coevolution - influence of closely associated species on each other in their evolution consensus tree - provides estimate for level of support for each clade Continuous variation - variation in phenotypic traits that can't be grouped into discrete categories (ex. weight, height, etc) convergent evolution - the independent evolution of similar traits in distantly related organisms due to adaptation to similar environments and lifestyles Cuvier - comparative anatomy and extinction directional selection - mode of natural selection, extreme phenotype favored over others: causes allele frequency to shift over time ex. dark moths when smog increases dispersal - -movement of individuals from birth site to breeding site (natal disp) -from breed to breed (breeding disp) disruptive selection - -pushing for both extremes, but average may stay the same -mating with who you look like Diversity (t + 1) - = Diversity (t) + α - Ω