Geologic Time

The table below is a compilation the history of the Earth, based on a large number of dated fossil finds and rock formations. Periods of time in the Earth's history are traditionally divided into eons, eras, periods, and epochs, each of which occupies a particular absolute time range, in millions of years ago (MYA) based on radiometric dating, and during which particular types of fossils are found.

Remembering that the vertical axis of your hypothesis diagram represents a time scale, you should compare the sequence of appearance of various groups here with what is shown in your hypothesis.

Beginning, Eon Era Period Epoch MYA before Events in fossil record present P End of last ice age Holocene 0.011 H Quaternary (civilization, history) A Pleistocene 1.8first humans N E Pliocene 5.3first apes R Diversification of horses, deer, Miocene 23.8 O etc. Cenozoic Z first monkeys, various groups of Oligocene 33.7 O mammals I Tertiary C Eocene 54.8Early whales, ungulate ancestors

extinction of dinosaurs, lots of Paleocene 65 new mammals first flowering plants, oldest Cretaceous 144 mushroom fossils Jurassic 206first birds Mesozoic first conifers, dinosaurs, and Triassic 248 mammals

Paleozoic mammal-like reptiles, first Permian 290basidiomycete fungi (phylum including mushrooms) Pennsylvanian 325first reptiles Carboniferous Mississippian 354first amphibians, insects

Devonian 417First land vertebrates, first ferns First land plants and land Silurian 443invertebrates, first fish with jaws, first land fungi. Ordovician 490first vertebrates (fish).

Lots of new invertebrate phyla -- Cambrian 543 mollusks, trilobites, etc.

P Upper 900first multicellular organisms R Middle 1600first eukaryotes E Proterozoic C Lower 2500first bacterial plankton A M Archean 3800first bacteria B R oldest Solar System rocks -- no I Hadean 4500 A fossils N

Adapted from Strickberger, Evolution, with additional information from (and links to) University of California Museum of Paleontology.