Evolution, A change in species over time, Species that evolve faster, Have faster generation times (reproduce earlier in life), Artificial Selection, Human choose favorable traits and guide the evolution of a species. Ex: Wolf -> dogs, Mutation, Change in DNA - give rise to new traits, Favorable vs unfavorable traits, Favorable = drive evolution and become a part of the species Detrimental - edited out of a population, Genetic Diversity, Variation of traits within a species, Fossil Record, Evidence of evolution - track changes in a species layer to layer over time, Biogeography, Tracking changes in species as they move from one environment to another across the planet, Embryology, Tracking developmental stages in common across species. More stages in common = more closely related, Comparative Anatomy, Compare structures that species have in common (common blueprint). Forelimbs of mammals - bones found in same sequence, Molecular Evidence, DNA - more base pairs in common = closely related, Gene Flow, Traits emerge in one population and flow to another "herd" as members reproduce with other populations. Population evolve together., Genetic Drift, Populations become isolated from each other and don't reproduce with eachother. Over time mutations/DNA differences add up until they are no longer able to reproduce with each other since they are now separate species., Speciation, The emergence of a new species, Behavioral Isolation, Organisms no longer recognize each other as potential mates due to courtship differences. Ex songs, dances etc, Temporal Isolation, Organisms of same species go through mating seasons at different times and no longer reproduce with each other., Geographic Isolation, Organisms can no longer reach each other to reproduce. DNA differences add up over time, Bottleneck Effect, Genetic Diversity built up over hundreds of thousands of years is lost. Left with less diversity = more likely to go extinct if environment changes, Sexual Selection/Non-Random Mating, Usually the female is choosing what variation is favorable. Males without that version do not reproduce and the lack of the trait dies with him. Males with the trait reproduce and pass trait on. Ex Peacocks

5.c Evolution

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