Scientists say Earth’s sixth mass extinction wave has begun – and we can do something about it

Several waves of mass extinctions have swept the Earth, and according to a research group, we’re now at the beginning of one of those waves – the difference is that they now believe we as humans are responsible for it. Earlier, we also wrote about mass extinction events on Earth and the supposed reasons behind them:

Perhaps because of a mysterious celestial body, but every twenty-seven million years a massive extinction sweeps the planet
Dark matter, a mysterious brown dwarf deflecting asteroids, and terrestrial volcanic activity, plus an incomprehensible combination of these, are suspected to be behind Earth’s periodic mass extinctions. However, the extinction event that may occur now is different from previous events.

We also described in our article above that a wave of mass extinction means that the planet is losing a significant proportion of its biodiversity faster than it can be replaced—and all this relatively (from a geological-historical point of view) very quickly: it happens in less than 2.8 million years. Of course, species are always disappearing, the extinction of 5-10 percent of the planet’s species over the course of a million years is considered normal, however, any rate higher than this, say 10 percent species extinction, can be considered a significant event.

Paleontologists have identified five major mass extinction events based on fossils. At the end of the Ordovician period, about 443 million years ago, an estimated 86% of all marine species had disappeared. At the end of the Devonian period, about 360 million years ago, 75% of all species became extinct. At the end of the Permian period, about 250 million years ago, the most serious extinction event to date occurred, with an extinction rate of 96%. At the end of the Triassic period, about 201 million years ago, 80% of all species disappeared. The most famous mass extinction occurred at the end of the Cretaceous period, about 65 million years ago, when 76% of all species, including the dinosaurs, became extinct. In addition to these mass events, there were also smaller extinction events, all of which were more significant than normal.

According to the team led by Robert Cui, a professor at the Pacific Research Center for Biological Sciences at the University of Hawaii, a sixth event caused by human activity is likely to start now. like this Researchers write based on a vice article:

A sixth mass extinction on land and fresh water looks increasingly likely.

According to the researchers, denying this claim means someone is flying upside down in the mountains of data available as evidence, and there is “no room for doubt” anymore. Cui and colleagues cite a number of studies that rank species extinctions across masses, but the article is primarily based on their research on molluscs, the family of invertebrates that includes snails and clams. They say this focus balances the disproportionate attention given to vertebrates such as birds and mammals on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species. The researcher added:

Perhaps the IUCN information about bird and mammal extinctions is completely accurate. However, a tiny percentage of invertebrates, such as insects, snails, spiders and crustaceans, which make up 95 percent of animal diversity, have not been properly evaluated.”

Previous studies have also used IUCN data to debunk the idea that we are entering a sixth mass extinction. Cui and his colleagues cite extinction rates for land snails and molluscs and claim that this wave of extinction is already about to begin. Extrapolating from the data, the team came to the conclusion that 7.5-13 percent of species may have gone extinct since 1500 — a significant percentage, especially in such a short time.

In the article linked above, we also wrote about the study that argued that, on the one hand, mass extinctions should not be expected, and on the other hand, that climate change alone will not cause such mass extinctions in the near future, although that is still the current rate For species extinctions two degrees higher than what would be considered normal. However, the researchers add, these numbers do not refute the fact that we are currently heading towards such an event. According to the study, the change we cause is less severe than an asteroid impact, but could still trigger a smaller extinction event. This means that some species will slowly but surely disappear from the planet, but we will not reach the point where 60 percent of all species on Earth will disappear – which is therefore considered a mass extinction. During the current research, Cui and his team claimed, based on the extinction of various invertebrates, that it was indeed a mass extinction.

Incidentally, many ecologists have already drawn attention to the fact that the extinction rate determined at the time is only an estimate and may be inaccurate, mainly due to the omission of records from invertebrate species.

(photo: Pixabay/rostichep)