The mass extinction of animals was caused by a decrease in global oxygen availability, according to a new study.
The research spearheaded by Scott Evans, a researcher in the Department of geosciences, part of the Virginia Tech College of Science, shows the earliest mass extinction of 80% of animals. The loss of many different types of animals, however those whose body plans and behaviors indicate that they relied on significant amounts of oxygen seem to have been hit particularly hard. All mass extinctions in the geologic record are thought to have been controlled by the environment.
Evans' work was published in a peer reviewed journal. The study was co-authored by Shuhai Xiao, a professor in the Department of Geosciences, and several researchers led by Mary Droser, a professor in the Department of Earth and Planetary Sciences.
"Environmental changes, such as global warming and deoxygenation events, can lead to massive extinction of animals," said Xiao, who is an affiliated member of the Global Change Center. This work on the first extinction documented in the fossil record is one of many examples of this. The study tells us about the long-term impact of the environment on the biosphere.
There was a drop in global oxygen. It's still up for discussion. We don't really know how this happened. The animals that go extinct seem to be responding to decreased global oxygen availability.
Evans and Xiao's study is more timelier than thought. The loss of oxygen availability is affecting the world's fresh waters. What is the reason? Climate change contributes to the warming of waters. Warming waters deplete fresh water's capacity to hold oxygen, while the breakdown of nutrients in run off by freshwater organisms depletes oxygen.
"Our study shows that, as with all other mass extinctions in Earth's past, this new, first mass extinction of animals was caused by major climate change - another in a long list of cautionary tales demonstrating the dangers of our current climate crisis for animal life."
The end of the Cryogenian Period and the beginning of the Cambrian Period were both bookended by the Ediacaran Period. There is a break in the geologic record before the extinction event.
According to Xiao, there are five mass extinctions that stand out in the history of animals.
Mass extinctions are important steps in the evolution of life on this planet, according to the study. The result of the mass extinction was a series of shifts in the environment. We think that decreased global oxygen availability is the cause of the extinction. The authors wrote that this suggests that abiotic controls have had a significant impact on diversity.
The creatures that died in the extinction event would have looked like fossils. Evans said they looked strange.
Evans said that these organisms occur so early in the evolution of animals that they appear to be experimenting with different ways to build large, sometimes mobile, multicellular bodies. The fossils we find don't fit nicely into the way we classify animals today. The extinction may have paved the way for the evolution of animals.
The study was one of many that came out of the COVID-19 epidemic. Evans, Xiao, and their team were unable to get access to the field so they decided to put together a global database. There was a lot of speculation as to whether there would be an extinction at this time. We wanted to try and test those ideas. Evans made a statement. Much of the data used in the study was collected by Droser.
The first major animal extinction across the Ediacaran White Sea-Nama transition was caused by environmental drivers. The DOI is 10.1073/pnas.2207
Journal information: Proceedings of the National Academy of Sciences
All Rights Reserved © 2024
