1. Tree of Evolution Conditions of Early Earth (greater radiation and igneous activity) lead to the synthesis of abiotic (non-living) molecules – nucleic acids (RNA) & amino acids led to the formation of protobionts (droplets with membranes that maintained the internal environment) origin of self replication to produce new organisms – Sources for the carbonaceous molecules could have come from meteorites or from the substrate. Environment in early Earth (~3.6 billion years ago) was a reducing environment (electron adding) creating the opportunity for the formation of new molecules from methane and ammonia.

2. Fossil record Prokaryotes – Stromatolites - beds of sediment containing the byproducts of bacterial metabolism (shows blooms followed by extinctions) oldest ~3.5 billion years - anaerobes – halophiles – methanogens

3. Fossil Record – photosynthesis and the oxygen revolution (cyanobacteria) prokaryotes start using oxygen as a source of reducing energy to form new molecules photoautotrophs

4. Fossil Record Eukaryotes (~2.1 billion years ago) – arose from the symbiotic relationship and transfer of genetic material between prokaryotes – organisms resemble simple single celled algae – Endosymbionts - mitochondria & plastids endosymbionts take over the role of energy making paving the path for multicellular organisms genetic annealing (combining of genomes) and colony formation leads to specialization and the multicellular organism multicellular organisms (~1.5 billion years ago) – most confined to areas of water and heat (snowball Earth hypothesis) resembling small algae – Cambrian explosion (explosion of life ~ 700mil years ago)

5. Geologic time scale eon - longest division – Archeon - 1st eon of Earth ~3.9 to 2.5 billion years ago – Proterozoic - lasted for the next 2 billion years – Phanerozoic - most resent with evidence of life era - there are three eras per eon – Paleozoic - ~543 million years ago "Age of Invertebrates" fossils of both land and plants – Mesozoic - ~248 million years ago "Age of Reptiles" dinosaurs – Cenozoic - ~most recent "Age of Mammals" appearance of humans

6. Geologic time scale periods – Precambrian - all periods before the paleozoic era rocks lack index fossils fossil evidence is contained in stromatolites - layers of bacteria and algae content is high in valuable metals - Au, Ag, Cu,... – Cambrian invertebrates trilobites is the most common index fossil ~500 million years ago

7. Geologic time scale Ordovician – invertebrates – graptolites are the most common index fossil - lived in colonies Silurian - appearance of terrestrial animals Devonian - Age of the Fishes - 1st fossils of lungfish found Carboniferous - appearance of reptiles and vertebrates

8. Geologic time scale Permian - formation of Pangaea - nearly 1/2 of known fossils extinct by the end of the period – marks the end of the Paleozoic era Triassic - Jurassic - Cretacious are periods of the Mesozoic – rise and fall of the dinosaurs Paleogene, Neogene, & Quarternary are periods of the Cenozoic – formation of modern climate features and the rise of man

9. Geologic time scale Epochs (part of the Cenozoic) – Holocene… Historical time begins (.01mil yrs) – Pleistocene… Ice Ages… Humans appear (1.8mil yrs) – Pliocene… Origin of genus Homo (5.3mil yrs) – Miocene… Continued radiation of species (23mil yrs) Apelike ancestors of humans – Oligocene… Origin of primate groups (33.9mil yrs) – Eocene… Angiosperms dominate (55.8mil yrs) – Paleocene… massive radiation of mammals, birds, & insects (65.5mil yrs)