1. Evidence for EVOLUTION

2. FOSSILS Preserved remnants of dead or extinct organisms. Organized in strata of sedimentary rocks 3.5 bya- prokaryotes * Vertebrates: fish, amphibians, reptiles, birds and mammals EVIDENCE FOR EVOLUTION

3. COMPARATIVE ANATOMY- A Homologous structures: Similar structures, different functions Comparison of body structures in different species Show signs of common descent Compare forelimbs of humans, cats, whales, bats Go to campbell 22F

4. EVIDENCE FOR EVOLUTION COMPARATIVE ANATOMY- B Analogous structures: different structures with same function Have no common ancestor. Example: bird wing-feather and bone bat wing- bone and skin Insect wing- chitin membrane

5. EVIDENCE FOR EVOLUTION COMPARATIVE EMBRYOLOGY Study of structures that appear during development of different organisms. Closely related- more similarities Ex.: fish, frogs, snakes, birds apes all have pharyngeal gill slits early in development. Later- slits develop into gills (fish), skull bones, and voice box (mammals).

6. EVIDENCE FOR EVOLUTION MOLECULAR BIOLOGY Comparison of nucleotide sequences between species. DNA is universal More similarities, more closely related GATTACACAG GATAACACCG Compare the nucleotide sequences between 2 species

7. EVIDENCE FOR EVOLUTION BIOGEOGRAPHY Geographical distribution of the species. (the different places where species are found). Darwin’s 1 st clue that organisms evolve from common ancestors. Galapagos islands- more tropical than S. America, yet organisms resembled those from S.A.