a catastrophic, widespread perturbation where major groups of species become extinct over a relatively short time compared to normal background extinctions e.g., the K-T event, 65 million years ago, correlated with the disappearance of the dinosaurs.
Mass extinction is the process in which huge numbers of species die out suddenly. The dinosaurs (and many other species) became extinct, probably because of an asteroid that hit the Earth.
The name given to a period of especially high rates of extinction of species. Several such events are seen in the fossil record. Some palaeobiologists suggest that we are on the brink of another mass extinction today, caused by human activities
Catastrophic, widespread, often global event in which major groups of species are wiped out over a short time compared with normal (background) extinctions. Compare background extinction, mass depletion.
A large extinction of species, often plants and animals, occurring on a global scale. Analysis of fossil abundance suggests a mass extinction to have occurred at the end of the Cretaceous period.
a relatively sudden, global decrease in the diversity of life forms
A mass extinction is most simply defined as a period of time in which the number of extinctions drastically rises (Raup 801). The extinction of the dinosaurs is a classic example, but this episode is not the only mass extinction recorded in the fossil record. In fact, there are many more, and in recent years several palaeontologists have suggested that these mass extinctions are periodic, or occur in a regular cycle. For more, please read "What Factors May Lead to Periodic Mass Extinctions?" By Steve Brusatte
A phenomenon in which numerous species cease to exist at or around the same time, usually as the result of a natural calamity.
A point in the geological record where a large number of species (or individuals) disappear at once. There are many reasons for mass extinctions; disasters, rapid climate changes, and pandemic disease toname a few. Several extinction events occured during the Mesozoic Era.
An event in which large numbers of species die out in a very short time across the whole of the Earth. The K-T event was one of the 'Big Five', the five largest mass extinctions.
n: A catastrophic, widespread -- often global -- event in which major groups of species are wiped out over a relatively short period when compared to normal ( background ) extinction rates. There have been five major mass extinctions, of natural causes (in at least one case due to an asteroid impacting the earth), in the earth's history. We are now entering a sixth great mass extinction, this time of unnatural causes... human activities.
A time during which extinction rates are generally accelerated so that more than 50% of all species then living become extinct; results in a marked decrease in the diversity of organisms.
Mass extinction is the process in which huge numbers of species die out suddenly. The dinosaurs (and many other species) went extinct during the K-T extinction, which was probably caused by an asteroid colliding with the Earth.