Evolution of species

1. Evolution of species

2. Cladistics • A simple and objective way of constructing phylogenies (phylogenetic trees) • Focus on shared derived characters • Clade – group of organisms related by descent • Synapomorphy – shared derived character of a clade • Cladogram – the branching diagram representing the phylogeny • plesiomorphy - ancestral traits • apomorphy - derived character evolved within a clade

4. Mode of speciation • Gradualism vs. punctuated equilibrium

6. Sympatry vs. allopatry • Sympatry – species that co-occur in space and time • Allopatry – species that do not overlap in distribution • Speciation most readily occurs in allopatry

7. Islands • Importance to speciation due to isolation

8. Ring species

9. Isolating mechanisms

14. The evolution of life

16. Angiosperms Gymnosperms Pteridophytes

17. Day 1 in the life of earth Evolution of life First Bacteria 1 Billion Sudden increase in Diversity 4 Billion Today 4.5 Billion

22. - 3500 Pre-Cambrian– protosynthesis, prokaryotes, first eucaryotes, multicelluar organisms. • 545 Cambrian – huge increase in diversity, first algae, first vertebrates, invertebrates dominate. • 500 Ordovician – plants colonize land • 440 Silurian – fish, insects plus other inverts colonize land • 410 Devonian – amphibians colonize land • 355 Carboniferous – Extensive forests, amphibians dominate on land, first reptiles • 290 Permian – Pangea forms, reptiles dominate land • 250 Triassic – early dinosaurs, first mammals • 205 Jurassic – continents begin to separate, first birds, flowering plants • 145 Cretaceous – flowering plants dominate land, dinosaurs go extinct • 65 Tertiary – continents near present position, flowering plants, birds and mammals, pollinating insects • 1.8 Quaternary – repeated advance and retreat of glaciers, humans, large mammals and birds go extinct.