| A | B |
| Charles Darwin wondered about the Galapagos finches | if they were once part of the same species on the same island |
| Why do animals survive that are best suited for their environment? | They have inherited adaptations that are most fit for the environment |
| Part of Darwin's theory of evolution by Natural Selection | more offspring are produced than survive to adulthood |
| Evidence for Nat Sel today that wasn't available to Darwin | DNA |
| How natural selection lead to evolution | Helpful traits accumulate among surviving members of species |
| If genes are helpful | they increase in frequency |
| If organisms do not have the traits necessary for survival in an environment | they become extinct |
| Homologous structures | show common ancestry |
| Vestigial structures | organs that used to have a purpose but no longer do |
| Phenotypes | directly influence the success of an organism in its environment |
| Population evolves when allele frequency... | changes |
| Temporal Isolation | organisms breed at different times |
| Geographic Isolation | species are separated by geographic barriers |
| Behavioral Isolation | species have different mating calls/behaviors |
| Earth's Early Atmosphere | More carbon dioxide; little to no oxygen |
| Since DNA of chimps and humans are so similar | they had a recent common ancestor |
| Skeleton of bipedal hominids | bowl-shaped pelvis, S-shaped spine, no opposable toes, femurs angled inward |
| What is true of embryos of closely related species? | They develop in much the same way |