According to a new study published in Historical Biology, researchers have unveiled an event of mass-extinction which was previously underestimated. The records show 5 of such events, each marking the end of a geological period. These events shaped the earth as we see it now. They are:
- Cretaceous (66 million years ago)
- Triassic (201 million years ago)
- Permian (252 million years ago)
- Late Devonian (372 million years ago)
- Ordovician (443 million years ago)
The latest study is based on the analysis of records from Guadalupian epoch or middle Permian period. This period stretched from 272 to 260 million years ago from the present date. The analysis reveals that the event instantly wiped out life from both the land and the sea. According to Michael Rampino, Professor at the New York University of Biology, it is essential to know the time of the event of mass extinction to understand the cause that initiated it. He also stated that these events note devastating environmental upheavals especially massive flood-basalt eruption. The impact of these events covered million squares of kilometers with thick lava.
What Kept This Event Evade Researchers’ Attention?
The researchers believe that the end-Guadalupian extinction event took place simultaneously with Emeishan flood-basalt eruption that produced Emeishan Traps in South West of China. Nevertheless, this eruption had a similar impact on the life present at that time as other events had — total annihilation. As a result of the loss of the records and evidence that contained the proof of the impact, the event remained in anonymity. According to Rampino, the massive eruption in this event released huge amount of greenhouse gases, especially CO2 and methane, disrupting the ecological balance.
Now with advanced technologies and recently discovered fossils, researchers claim the loss of life in this event makes it stand in the list of mass-extinction events. This raises the total count of the events to six from five.