Timeline of the evolutionary history of life
From The Art and Popular Culture Encyclopedia
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This timeline of the evolution of life outlines the major events in the development of life on the planet Earth (See Organism). 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.
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Basic timeline
The basic timeline is a 4.5 billion year old Earth, with (very approximate) dates:
- 3.8 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 the genus Homo,
- 200,000 years since humans started looking like they do today,
- 25,000 years since Neanderthals died out.
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
This timeline of the evolutionary history of life represents the current scientific theory outlining the major events during the development of life on planet Earth. In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization, from kingdoms to species, and individual organisms and molecules, such as DNA and proteins. The similarities between all present day organisms indicate the presence of a common ancestor from which all known species, living and extinct, have diverged through the process of evolution.
See also
- Evolution of fungi
- Evolution of plants (timeline)
- Geologic time scale
- History of the Earth
- Natural history
- Sociocultural evolution
- Timeline of human evolution
- Timeline of natural history
Further reading
- The Ancestor's Tale by Richard Dawkins, for a list of ancestors common to humans and other living species