3. Phanerozoic- 550 million to present. Formation of plants, reptiles, mammals, birds, humans, primate groups
What are the three eras of the Phanerozoic eons and characteristics of each era?
1. Paleozoic- Vascular plants appear, marine algea, repitile, bony fishes
2. Mesozoic- Age of reptiles, dinosaures, flowering plants, cone bearing plants, gymnospears
3. Cenozoic- mammals, birds, pollinating insects, angiosperm, primates, humans, ice ages
When and what was the first sign of life?
3.5 billion years ago- Stromatolites- layered rocks that form when certain prokaryotes bind thin films of sediment together. Early prokaryotes lasted from 3.5 billion to 2.1 billion.