Common Ancestry Evolution Evolution is the process of

Common Ancestry

Evolution • Evolution is the process of change through time. • It is the process by which modern organisms have descended from ancient organisms.

Evidence of Evolution 1. 2. 3. 4. Fossil Record Anatomical Record Molecular Record Artificial Selection

1. Fossil Record • Shows change over time • Shows a series of organisms have lived on Earth • Fossils tell a story

2. Anatomical Record • Animals with different structures on the surface, but when you look under the skin… it tells an evolutionary story of common ancestors. – Homologous structures – Analogous structures – Vestigial structures – Comparative embryology

Homologous Structures • Structures that come from the same origin • homo- = same • -logous = information • Forelimbs of human, cats, whales, & bats – same structure • on the inside – same development in embryo – different functions • on the outside – evidence of common ancestor

Analogous Structures § Analogous structures u look similar § on the outside same function u different structure & development u § on the inside different origin u no evolutionary relationship u

Analogous Structures § Dolphins: aquatic mammal § Fish: aquatic vertebrate both adapted to life in the sea u not closely related u

Vestigial Organs • Structures on modern animals that have no function – remains of structures that were functional in ancestors – evidence of change over time • some snakes & whales have pelvis bones & leg bones of walking ancestors • eyes on blind cave fish • human tail bone

Vestigial Organs Because they used to walk on land!

Comparative Embryology • Development of embryo tells an evolutionary story – similar structures during development

3. Molecular Record • Comparing DNA & protein structure – everyone uses the same genetic code! • DNA

Cladogram • A diagram used to show relations between organisms • Shows which traits are shared and which not…

4. Artificial Selection • How do we know natural selection can change a population? – we can recreate a similar process – “evolution by human selection”

Selective Breeding Humans create the change over time “descendants” of the wolf

Artificial Selection Gone Bad! • Unexpected consequences of artificial selection Pesticide resistance Antibiotic resistance

Artificial Selection Gone Bad! • Spray the field, but… – insecticide didn’t kill all individuals • variation – resistant survivors reproduce – resistance is inherited – insecticide becomes less & less effective

Evolution of Dance and Technology… • Evolution of Dance – http: //www. youtube. com/watch? v=d. MH 0 b. H ei. RNg • Evolution of Dance 2 – http: //www. youtube. com/watch? v=in. LBPVG 8 o. EU&feature=fvwrel