Biology Exam 3 - Bio2

evolution

change in genetic composition of a population over time

mutation

change in DNA sequence

gene flow

transfer of alleles between populations

genetic drift

random change in allele frequencies over time

bottleneck affect

random large decrease in a population which leads only a random few to survive

founder effect

random sample moves somewhere else —> random sample of og alleles

natural selection

evolutionary process by which individuals best adapted to their environment survive and reproduce

differential fitness of individual phenotypes within a population

artificial selection

selective breeding of organisms by humans

homology

similar features from shared ancestry

vestigial structures

lost original function

fitness

relative survival and reproduction success of an individual compared to others

adaptation

heritable trait that evolved in a population through natural selection

noun and verb

hardy weinberg

p + q = 1

stabilizing selection

mean phenotype has higher fitness than tail ends

gets rid of genetic variation

directional selection

one extreme has a higher fitness than mean

linear

disruptive selection

both extreme tail ends have higher fitness than mean

heterozygote advantage

multiple alleles so higher fitness —> maintain multiple alleles

temporally variable selection

changing environments favor different phenotypes at different times

prevent allele fixation

spatially variable selection

different local environments favor different phenotypes