Not entirely know, but obvious candidates are extrogenous events like a meteorite strike. Climate change via natural processes (eg Millankovitch cycles). There is also some that suggestion that mass extinctions may occur merely due to the fact that complex dynamic systems (like a global ecosystem) exihibits exitinctions events of varying magnitudes or fluctuations. Here mas extinctions are merely chain reaction of smaller extinction events as an individual species extinction (caused by small extrogeneos or introgeneous factors) cascades through an ecosystem. (See Self-organized criticality and punctuated Equilibrium.
every 27-33 million years
The role of mass extinction in evolution. At the most basic level, mass extinctions reduce diversity by killing off specific lineages, and with them, any descendent species they might have given rise to. ... But mass extinction can also play a creative role in evolution, stimulating the growth of other branches.
The role of mass extinction in evolution. At the most basic level, mass extinctions reduce diversity by killing off specific lineages, and with them, any descendent species they might have given rise to. ... But mass extinction can also play a creative role in evolution, stimulating the growth of other branches.
The factors that generally cause mass extinction are changes in the natural ecosystem of the species. This may make it difficult for the species to reproduce and to stay alive.
Not every animal went extinct, only some, such as the dinosaurs.
The end of the last few Era's have been marked by mass extinctions.Cenozoic Era(65.5Ma to Now) - Current EraMesozoic Era(251 to 65.5Ma) - Cretaceous/Tertiary Extinction Event.Paleozoic Era(542 to 251Ma) - Permian/Triassic Extinction Event (Great Dying)Neoproterzoic Era(1000 to 542Ma) - Mass extinctions of many of the 1st multi celled animals.Before this it gets less certain. The dates are generally based on numerical ages rather than any particular events. Earlier Eras include.Mesoproterzic Era(1,600 to 1,000Ma)Paleoproterzoic Era(2,500 to 1,600Ma)Neoarchean Era(2,800 to 2,500Ma)Mesoarchean Era(3,200 to 2,800Ma)Paleoarchean Era(3,600 to 3,200Ma)Eoarchean Era(4,000 to 3,600Ma)Before this there are no named eras. It is known as the Hadean Eon(4576 - 4,000Ma).
Mass extinction. A mass extinction typically occurs after a catastrophic global event. This event could be a bolide impact (such as the impact 65 million years ago that killed the dinosaurs, the most famous example of a mass extinction), increased volcanism, climate change, or something similar.
There were five major extinction events in the past. They are called the Cretaceous-Tertiary (or K-T) extinction event, the late Devonian mass extinction, the Permian mass extinction, the Ordovician-Silurian mass extinction and the Triassic-Jurassic mass extinction event.
Mass depletion is an event in which extinction rates are higher than normal but not high enough to be classified as a mass extinction.
No, child, I was not a witness to the Permian Extinction. The Permian extinction event is the only known mass extinction of insects. The Permian extinction event occurred about 252 million years ago.
Which mass extinction? There have been five such events. The first one, the Ordovician-Silurian extinction event occurred before the Devonian. The Late Devonian event occurred during the Devonian. All other mass extinctions occurred after the Devonian.
We are still not sure what caused the mass extinction of the dinosaurs, though an asteroid impact seems to be the popular theory.Scientists believe we may be heading towards another mass extinction event.
A mass extinction or extinction event. For instance the death of the dinosaurs is the Cretaceous-Tertiary event (or K-T event for short).
The most devastating mass extinction occurred in the Late Permian (~250 million years ago).
An asteroid impact
mass extinction
A mass extinction
No evidence of the extinct lifeforms appears in the stratigraphic record immediately following the extinction event.