Earth May Be Experiencing a Seventh Mass Extinction.

How May Earth Experience a Seventh Mass Extinction? Thousands of species disappear from the Earth's biota yearly due to global extinction. Scientists now believe that the first such event occurred millions of years earlier than previously thought because of environmental changes.

As the Cretaceous period ended 66 million years ago, most dinosaurs mysteriously vanished. Before then, some 252 million years ago, the vast bulk of Earth's creatures died out between the Permian and Triassic periods.

The University of California at Riverside and Virginia Polytechnic Institute and State University found a similar extinction 550 million years ago during the Ediacaran period. This study was published in the Proceedings of the National Academy of Sciences.

An actual "mass extinction" has yet to be determined, but the percentage of creatures lost is comparable to those of these earlier episodes, including the ongoing one.

About 80% of all Ediacaran animals, the first sophisticated, multicellular living forms on the planet, vanished, and scientists believe environmental changes are to blame.

Chenyi Tu, a paleoecologist from the University of California, Riverside, and co-author of the study, explains that "geological data suggest that the world's oceans lost a lot of oxygen" and that the few surviving species had bodies adapted for lower oxygen environments.

Creatures who perished in this first event were soft-bodied and did not survive well in the fossil record, making their extinction story harder to piece together than those of the following events.

UCR paleoecologist and study co-author Rachel Surprenant said, "We suspected such an event, but to prove it, we had to assemble a massive database of evidence." The group gathered data on the habitat, body size, food, mobility, and habits of every Ediacaran species known to science.

Furthermore, in the discussion of Earth May Be Experiencing a Seventh Mass Extinction, This study aimed to debunk the theory that the massive extinction at the close of the Ediacaran period was due to causes other than climate change. A lack of proper data collection or a shift in animal behavior due to, say, the introduction of predators were previously proposed as possible causes for the occurrence.

The animals "did not just move elsewhere or get eaten — they died out," as Chenyi put it because their geographic distribution over time is visible. We've established, with complex data, that the biotic community has been dwindling.

They measured dead organisms' surface area to volume ratio, indicating oxygen depletion played a role in the fatalities. Heather McCandless, a UCR paleoecologist and research co-author, explained that "if an organism has a greater ratio, it can get more nutrients" and that the bodies of the creatures who did survive into the following era were modified in this way.

Mary Droser, a paleoecologist at the University of California, Riverside, and her graduate student, Scott Evans, now of Virginia Tech, are responsible for this effort. The next session will focus on these creatures' evolutionary beginnings rather than their ultimate demise.

By today's standards, life in the Ediacaran would seem bizarre. Many creatures could move, but they were utterly alien to modern life. Disc-shaped Obamus coronatus and raisin-like Attenborites janeae, both named for former president Barack Obama and English naturalist Sir David Attenborough, respectively.

Despite being the first test subject for evolution on Earth, these creatures only survived for a few million years. Droser emphasized how quickly this was in the context of evolution.

While the exact cause of the dramatic drop in atmospheric oxygen levels at the epoch's conclusion remains a mystery, we can be confident that shifts in Earth's environment have the potential to destabilize and even wipe out life on the planet at any time. All past and current mass extinctions can be traced back to this change category.

Phillip Boan, a geologist at UC Riverside and co-author of the study, stated, "There's a strong association between the success of life and, to quote Carl Sagan, our 'pale blue dot.'"

The end of the world can happen to anything. Boan said that while we plan for the future, we should consider the disastrous impacts of climate change on ecosystems.

Earth May Be Experiencing a Seventh Mass Extinction; stay tuned for more.