Evolutionary and Geological Timelines
by Niel Brandt

Evolutionary Timeline

(Myr ago)
4600Formation of the approximately homogeneoussolid Earth by planetesimal accretion
4300Melting of the Earth due to radioactive andgravitational heating which leads to itsdifferentiated interior structure aswell as outgassing of molecules such aswater, methane, ammonia, hydrogen, nitrogen,and carbon dioxide
4300Atmospheric water is photodissociated by ultravioletlight to give oxygen atoms which are incorporatedinto an ozone layer and hydrogen molecules whichescape into space
4000Bombardment of the Earth by planetesimals stops
3800The Earth's crust solidifies--formation of theoldest rocks found on Earth
3800Condensation of atmospheric water into oceans
3500-2800Prokaryotic cell organisms develop
3500-2800Beginning of photosynthesis by blue-green algaewhich releases oxygen molecules into the atmosphereand steadily works to strengthen the ozone layerand change the Earth's chemically reducing atmosphereinto a chemically oxidizing one
1600The last reserves of reduced iron are used up by theincreasing atmospheric oxygen--last banded ironformations
1500Eukaryotic cell organisms develop
1500-600Rise of multicellular organisms
580-545Fossils of Ediacaran organisms are made
545Cambrian explosion of hard-bodied organisms
528-526Fossilization of the Chengjiang site
517-515Fossilization of the Burgess Shale
500-450Rise of the fish--first vertebrates
430Waxy coated algae begin to live on land
420Millipedes have evolved--first land animals
375The Appalachian mountains are formed via a platetectonic collision between North America, Africa,and Europe
375Appearance of primitive sharks
350-300Rise of the amphibians
350Primitive insects have evolved
350Primitive ferns evolve--first plants with roots
300-200Rise of the reptiles
300Winged insects have evolved
280Beetles and weevils have evolved
250Permian period mass extinction
230Roaches and termites have evolved
225Modern ferns have evolved
225Bees have evolved
200Pangaea starts to break apart
200Primitive crocodiles have evolved
200Appearance of mammals
145Archaeopteryx walks the Earth
136Primitive kangaroos have evolved
100Primitive cranes have evolved
90Modern sharks have evolved
65K-T Boundary--extinction of the dinosaurs andbeginning of the reign of mammals
60Rats, mice, and squirrels have evolved
60Herons and storks have evolved
55Rabbits and hares have evolved
50Primitive monkeys have evolved
28Koalas have evolved
20Parrots and pigeons have evolved
20-12The chimpanzee and hominid lines evolve
10-4Ramapithecus exist
4Development of hominid bipedalism
4-1Australopithecus exist
3.5The Australopithecus Lucy walks the Earth
2Widespread use of stone tools
2-0.01Most recent ice age
1.6-0.2Homo erectus exist
1-0.5Homo erectus tames fire
0.3Geminga supernova explosion at a distance of roughly60 pc--roughly as bright as the Moon
0.2-0.03Homo sapiens neanderthalensis exist
0.05-0Homo sapiens sapiens exist
0.04-0.012Homo sapiens sapiens enter Australia fromsoutheastern Asia and North America from northeastern Asia
0.025-0.01Most recent glaciation--an ice sheet covers muchof the northern United States
0.02Homo sapiens sapiens paint the Altamira Cave
0.012Homo sapiens sapiens have domesticated dogs inKirkuk, Iraq
0.01First permanent Homo sapiens sapiens settlements
0.01Homo sapiens sapiens learn to use fire to castcopper and harden pottery
0.006Writing is developed in Sumeria

Geological Timeline

(Myr ago)
Archaeozoic (Archean)era5000-1500
Proterozoic era1500-545
PaleozoiceraCambrian period545-505
Ordovician period505-438
Silurian period438-410
Devonian period410-355
Carboniferous(Mississipian/Pennsylvanian) period355-290
Permian period290-250
MesozoiceraTriassic period250-205
Jurassic period205-135
Cretaceous period135-65
"Recent Life"
Tertiary periodPaleocene epoch65-55
Eocene epoch55-38
Oligocene epoch38-26
Miocene epoch26-6
Pliocene epoch6-1.8
QuarternaryperiodPleistocene epoch1.8-0.01
(Lower Paleolithic)0.50-0.25
(Middle Paleolithic)0.25-0.06
(Upper Paleolithic)0.06-0.01
Holocene epoch0.01-0

Taken from http://www.talkorigins.org/origins/geo_timeline.html

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