Evolutionary/Geological Timeline:
Copyright Niel Brandt 1994 (see copyright notice below)
Events relevant to Natural Fossil Reactors are shown in blue. All numbers are in millions of years.
Table 1: Archeozoic
4550-1500 million years
| 4550 |
Formation of the approximately homogeneous solid Earth by planetesimal accretion. |
| 4300 |
Melting of the Earth due to radioactive and gravitational heating which leads to its differentiated interior structure
as well as outgassing of molecules such as water, methane, ammonia, hydrogen, nitrogen, and carbon dioxide. First minerals form. |
| 4000 |
Bombardment of the Earth by planetesimals stops. |
| 3800 |
The Earth’s crust solidifies – formation of the oldest rocks found on Earth. |
| 3800 |
Condensation of atmospheric water into oceans |
| 3500-2800 |
Prokaryotic cell organisms develop |
| 3500-2800 |
Beginning of photosynthesis by blue-green algae which releases oxygen molecules into the atmosphere and steadily works to strengthen the ozone layer and change the Earth’s chemically reducing atmosphere into a chemically oxidizing one |
| 2400 |
Rise in the concentration of oxygen molecules stops the deposition of uraninites (since they are soluble when combined with oxygen) and starts the deposition of banded iron formations. |
| 2000 |
The Oklo natural fission reactor in Gabon commences operation for about 1 million years. |
| 1600 |
The last reserves of reduced iron are used up by the increasing atmospheric oxygen – last banded iron formations (since they are soluble when combined. |
Table 2: Protozoic
1500-545 million years
| 1500 |
Eukaryotic cell organisms develop. |
| 1500-600 |
Rise of multicellular organisms |
| 580-545 |
Fossils of Ediacaran organisms are made. |
Table 3: Paleozoic
545-250 million years.
| 545-505 |
Cambrian period |
| 545 |
Cambrian explosion of hard-bodied organisms |
| 528-526 |
Fossilization of the Chengjiang site |
| 517-515 |
Fossilization of the Burgess Shale |
| 505-438 |
Ordovician period |
| 500-450 |
Rise of the fish-first vertebrates |
| 438-410 |
Silurian period |
| 430 |
Waxy coated algae begin to live on land |
| 420 |
Millipedes have evolved – first land animals |
| 410-355 |
Devonian period |
| 375 |
The Appalachian mountains are formed via a plate tectonic collision between North America, Africa, and Europe |
| 375 |
Appearance of primitive sharks |
| 355-290 |
Carboniferous period |
| 350-300 |
Rise of the amphibians |
| 350 |
Primitive insects have evolved |
| 350 |
Primitive ferns evolve – first plants with roots |
| 300-200 |
Rise of the reptiles |
| 300 |
Winged insects have evolved |
| 290-250 |
Permian period |
| 280 |
Beetles and weevils have evolved |
| 250 |
Permian period mass extinction |
Table 4: Mesozoic
250-65 million years
| 230 |
Roaches and termites have evolved |
| 225 |
Modern ferns have evolved |
| 225 |
Bees have evolved |
| 200 |
Pangaea starts to break apart |
| 200 |
Primitive crocodiles have evolved |
| 200 |
Appearance of mammals |
| 145 |
Archaeopteryx walks the Earth |
| 136 |
Primitive kangaroos have evolved |
| 100 |
Primitive cranes have evolved |
| 90 |
Modern sharks have evolved |
Table 5: Cenozoic
65 million years ago
| 65-55 |
Paleocene epoch |
| 65 |
K-T Boundary – extinction of the dinosaurs and beginning of the reign of mammals |
| 60 |
Rats, mice, and squirrels have evolved |
| 60 |
Herons and storks have evolved |
| 55-38 |
Eocene epoch |
| 55 |
Rabbits and hares have evolved |
| 50 |
Primitive monkeys have evolved |
| 38-26 |
Oligocene epoch |
| 28 |
Koalas have evolved |
| 26-6 |
Miocene epoch |
| 20 |
Parrots and pigeons have evolved |
| 20-12 |
The chimpanzee and hominid lines evolve |
| 10-4 |
Ramapithecus exist |
| 6-1.8 |
Pliocene epoch |
| 4 |
Development of hominid bipedalism |
| 4-1 |
Australopithecus exist |
| 3.5 |
The Australopithecus Lucy walks the Earth |
Table 6: Quaternary
2 million years ago
| 2 |
Widespread use of stone tools |
| 2-0.01 |
Most recent ice age |
| 1.8-0.01 |
Pleistocene epoch |
| 1.6-0.2 |
Homo erectus exist |
| 1-0.5 |
Homo erectus tames fire |
| 0.50-0.25 |
Lower Paleolithic |
| 0.3 |
Geminga supernova explosion at a distance of
roughly 60% – roughly as bright as the Moon |
| 0.25-0.06 |
Middle Paleolithic |
| 0.2-0.03 |
Homo sapiens neanderthalensis exist |
| 0.06-0.01 |
Upper Paleolithic |
| 0.05-0 |
Homo sapiens sapiens exist |
| 0.04-0.012 |
Homo sapiens sapiens enter Australia from southeastern Asia and North America from northeastern Asia |
| 0.025-0.01 |
Most recent glaciation – an ice sheet covers much of the northern United States |
| 0.02 |
Homo sapiens sapiens paint the Altamira Cave |
| 0.012 |
Homo sapiens sapiens have domesticated dogs in Kirkuk, Iraq |
| 0.01-Today |
Holocene epoch |
| 0.01 |
First permanent Homo sapiens sapiens settlements |
| 0.01 |
Homo sapiens sapiens learns to use fire to cast copper and harden pottery |
| 0.006 |
Writing is developed in Sumeria |
Copyright Notice
The evolutionary/geological timeline data has been taken from a table (Evolutionary/Geological Timeline Version 1.0) prepared by Niel Brandt.
He would be grateful for factual, spelling, and grammar corrections. He would be grateful for suggestions as to how to better word specific entries so as to make them clearer. He is also keen to add interesting events to the timeline and would appreciate suggestions.
Please send any suggestions to: Niel Brandt niel@ast.cam.ac.uk
This data and the document from which it is taken is copyright Niel Brandt 1994. You are allowed to copy, distribute, and edit this document at will without any obligation as long as you do not remove this information. Reproduction and distribution for personal profit is not permitted.
