Search results
Results from the WOW.Com Content Network
Nuclear war is an often-predicted cause of the extinction of humankind. [1]Human extinction is the hypothetical end of the human species, either by population decline due to extraneous natural causes, such as an asteroid impact or large-scale volcanism, or via anthropogenic destruction (self-extinction), for example by sub-replacement fertility.
Published estimates for the 1st century (" AD 1 ") suggest uncertainty of the order of 50% (estimates range between 150 and 330 million). Some estimates extend their timeline into deep prehistory, to " 10,000 BC", i.e., the early Holocene, when world population estimates range roughly between 1 and 10 million (with an uncertainty of up to an ...
The largest extinction was the Kellwasser Event (Frasnian - Famennian, or F-F, 372 Ma), an extinction event at the end of the Frasnian, about midway through the Late Devonian. This extinction annihilated coral reefs and numerous tropical benthic (seabed-living) animals such as jawless fish, brachiopods, and trilobites.
In 50 billion years, if the Earth and Moon are not engulfed by the Sun, they will become tidelocked into a larger, stable orbit, with each showing only one face to the other. [ 104 ] [ 105 ] [ 106 ] Thereafter, the tidal action of the Sun will extract angular momentum from the system, causing the orbit of the Moon to decay and the Earth's ...
The timeline of the evolutionary history of liferepresents the current scientific theoryoutlining the major events during the development of lifeon planet Earth. Dates in this article are consensus estimates based on scientific evidence, mainly fossils. In biology, evolutionis any change across successive generations in the heritable ...
End-Jurassic (Tithonian) 145 Ma. No longer regarded as a major extinction but rather a series of lesser events due to bolide impacts, eruptions of flood basalts, climate change and disruptions to oceanic systems [16] Pliensbachian-Toarcian extinction (Toarcian turnover) 186-178 Ma.
t. e. Human history is the record of humankind from prehistory to the present. Modern humans evolved in Africa around 300,000 years ago and initially lived as hunter-gatherers. They migrated out of Africa during the Last Ice Age and had populated most of the Earth by the end of the Ice Age 12,000 years ago.
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period. It includes brief explanations of the various taxonomic ranks in ...