Earth has so far gone through five mass extinction events
-- scientists are worried we're on course to trigger a sixth -- and the deadliest one happened 252 million years ago at the end of the Permian geologic period.
SchwEngerl argues that the category of animals the study focuses on -- land vertebrates -- is too narrow to back up the claim that a major mass extinction event
is already underway.
However, recent faunal studies, especially on conodonts, suggest the extinction event
transcends the formational boundaries, and place the Permian-Triassic boundary within the basal or middle part of the Kathwai Member of the Mianwali Formation (see Pakistani-Japanese Research Group,1985; Wardlawand Mei, 1999).
We tend to focus so much on the extinction event
, not so much the recovery," Maher said, "but the recovery is also a really important piece that sets the stage for what happens in the next interval of life.
At first glance, they don't appear to record any major fossil changes indicative of a large-scale extinction event
, Lucas said.
A primeval volcanic range in western India known as the Deccan Traps, which were once three times larger than France, began its main phase of eruptions roughly 250,000 years before the Cretaceous-Paleogene, or K-Pg, extinction event
, the researchers report in the journal Science.
Some corporate leaders have been wondering whether they're facing the same extinction event
that hit Borders, Kodak, HMV, Blockbuster and others.
However, it's the impending sixth extinction that has Kolbert and others most concerned, for it is an extinction event
totally caused by humans.
Final chapters deal with the great K-T extinction event
and a short introduction to the allure of paleontology itself.
Now, we humans may be creating an extinction event
ourselves, which will have a major impact on the future of life on Earth.
It's up to residents of Cyprus to ensure that this Mass Extinction Event
The problem is getting worse and we were going to be facing an extinction event
of actually losing potentially three or four clubs - not to administration, but to liquidation.