Mechanisms of Evolution Concept 2 – Analyzing Descent with Modification: A Darwinian View of Life (Ch 22) Part 1: Introducing..... Sir Charles Darwin!

Try This! Explain this statement: “It is the population, not the individual that evolves.”

Descent with Modification You must know: How Lamarck’s view of the mechanism of evolution differed from Darwin’s Several examples of evidence for evolution The differences between structures that are homologous and those that are analogous, and how this relates to evolution The role of adaptations, variation, time, reproductive success, and heritability in evolution

Charles Darwin

Charles Darwin 1809-1882 Voyage on the HMS Beagle 1831-1836 Developed his Theory of Evolution by Natural Selection (as opposed to Lamarcks theory of evolution by inheritance of acquired characteristics)

Charles Darwin Observations Members of a population often vary greatly in their traits Traits are inherited from parents to offspring All species are capable of producing more offspring than their environment can support

Charles Darwin Inferences Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals

Charles Darwin Inferences This unequal ability of individuals to survive and reproduce will lead to the accumulation of favourable traits in the population over generations

Darwin vs Lamarck Lamarck thought that evolution worked through the inheritance of acquired characteristics... How is this different from Darwin’s natural selection?

Darwin vs Lamarck Let’s practice with the handout! Due next class 