15.3 Objective: to be able to explain how Darwin presented his case to others

publishing Darwin published “On the Origin of Species…” Darwin waited 25 yrs to publish---why? Wallace wrote an essay about the same topic, 25 yrs after Darwin thought of publishing

Nat’l selection Darwin proposed a mechanism for evolution natural selection!! He explained artificial selection people chose traits being passed on (dairy cows)

Nat’l selection For natural selection to happen Struggle for existence-> competition for resources Fitness- Ability to survive and reproduce

Nat’l selection Survival of the fittest- Adaptation- The best suited to the env. Will survive Adaptation- Inherited characteristic that increases chance of survival Can be- physiological, behavioral, structural

Nat’l selection Natural selection- Characteristic that helps an org. survive/reproduce in an env. Will be passed on Common descent- All living things were derived from common ancestors

evidence Evidence for evolution Fossil record comparing older fossils with newer ones to see changes Embryology- most embryos develop similarly at first.

evidence Homologous structures similar structure, different function Analogous structures similar function, different structure