Timeline of evolution

This timeline of the evolution of life outlines the major events in the development of life on the planet Earth. For a thorough explanatory context, see the history of Earth, and geologic time scale. The dates given in this article are estimates based on scientific evidence.

In biology, evolution is the process by which populations of organisms acquire and pass on novel traits from generation to generation. Its occurrence over large stretches of time explains the origin of new species and ultimately the vast diversity of the biological world. Contemporary species are related to each other through common descent, products of evolution and speciation over billions of years.

Basic timeline

The basic timeline is a 4.6 billion year old Earth, with (very approximately):
* 4 billion years of simple cells (prokaryotes),
* 3 billion years of photosynthesis,
* 2 billion years of complex cells (eukaryotes),
* 1 billion years of multicellular life,
* 600 million years of simple animals,
* 570 million years of arthropods (ancestors of insects, arachnids and crustaceans)
* 550 million years of complex animals
* 500 million years of fish and proto-amphibians,
* 475 million years of land plants,
* 400 million years of insects and seeds,
* 360 million years of amphibians,
* 300 million years of reptiles,
* 200 million years of mammals,
* 150 million years of birds,
* 130 million years of flowers,
* 65 million years since the non-avian dinosaurs died out,
* 2.5 million years since the appearance of Homo,
* 200,000 years since humans started looking like they do today,
* 25,000 years since Neanderthals died out.

Detailed timeline

:"Note that Mya means "million years ago"."

Hadean eon

3800 Mya and earlier.

Phanerozoic eon

542 Mya - present

The Phanerozoic eon, literally the "period of well-displayed life", marks the appearance in the fossil record of abundant, shell-forming and/or trace-making organisms. It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, which are divided by major mass extinctions.

Paleozoic era

542 Mya - 251.0 Mya

See also

* Evolutionary history of life
* Evolutionary history of plants
* Extinction events
* Geologic time scale
* History of Earth
* Natural history
* Sociocultural evolution
* Timeline of human evolution
* Timeline of plant evolution

Further reading

* "The Ancestor's Tale" by Richard Dawkins, for a list of ancestors common to humans and other living species

References

External links

* [http://wiki.cotch.net/index.php/History_of_the_Earth History of the Earth from EvoWiki]
* [http://www.ucmp.berkeley.edu Berkeley Evolution]
* [http://tolweb.org/Life_on_Earth/1 Tree of Life Web Project] - explore complete phylogenetic tree interactively
* [http://www.talkorigins.org/origins/geo_timeline.html A more compact timeline]
* [http://www.palaeos.com Palaeos - The Trace of Life on Earth]
* [http://sci.waikato.ac.nz/evolution/plantEvolution.shtml University of Waikato - Sequence of Plant Evolution]
* [http://sci.waikato.ac.nz/evolution/AnimalEvolution.shtml University of Waikato - Sequence of Animal Evolution]
* [http://www.wikitimescale.org/en/wiki/Evolution_on_Earth Graphical Timeline of evolution]
* [http://wiki.cotch.net/index.php/Geological_Timescale EvoWiki's geologic timescale and timeline of evolution.]
* [http://members.iinet.com.au/~drage/ History of Life on Earth]
* [http://exploringtime.org/?page=segments Exploring Time] from Planck Time to the lifespan of the universe
* [http://www.ensemble.ac.uk/projects/plantsci/timeline Interactive Plant Evolution Timeline] - from the University of Cambridge Ensemble Project