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bio 16-17 flashcards

Fossil Evidence of living things long ago
Artificial selection breeding animals to bring out specific traits (dogs or pigeons for example)
Adaptation A trait shaped by natural selection that increases an individuals chance of survival and reproduction
Analogous structure similar traits in unrelated species that evolved independently of one another
Vestigial structure A reduced form of a once more useful structure (human appendix)
Directional selection Natural selection that favors one extreme of a trait
Stabilizing selection Natural selection that favors the average version of a trait
Disruptive selection Natural selection that favors 2 extreme versions of a trait.
Genetic drift Random change in allele frequencies
Founder effect When a small subgroup of a population migrates to a new area, changing allele frequencies of that population
Polygenic trait A trait shaped by more than one set of genes
Genetic Equillibrium When allele frequencies in a population remain unchanged over time
Sexual selection Natural selection where females select males to mate with based on traits such as coloration and strength
Speciation When a population splits off and no longer interbreeds with the rest of its original species
Reproductive Isolation When individuals from 2 populations can no longer interbreed with each other
Behavioral Isolation When 2 populations who are capable of interbreeding develop differences in courtship rituals or other behaviors
Temporal Isolation When 2 or more species breed at different times which prevents interbreeding
Evolution The process by which organisms change over time
Fitness A measure of how well an organism can survive and reproduce in their environment
Natural selection Darwin's theory for how evolution occurs
Biogeography The study of where organisms live now and where their ancestors lived in the past
Homologous structure Traits that are similar between species that show inheritance from a common ancestor
Bottleneck effect When a population size decreases greatly and then rebounds, but genetic diversity is still greatly reduced
Hardy-Weinberg Principle allele frequencies in a population should remain constant unless 1 or more factors causes them to change
Species A group of individuals that can interbreed and have fertile offspring
Geographic Isolation When a physical barrier separates 2 populations and prevents interbreeding
Created by: 21guffeva