Mass extinctions can be cyclical

Mass extinctions can be cyclical
Mass extinctions can be cyclical
Anonim

Scientists from the United States have concluded that mass extinctions occur at regular intervals. These intervals average about 27.5 million years.

The work of specialists from New York University and the Department of Global Ecology of the Carnegie Institute of Science (USA) is published in the journal Historical Biology. In it, scientists emphasize that non-marine tetrapods (including amphibians, birds, reptiles and mammals) have experienced at least ten separate episodes of increased extinction over the past 300 million years (we are, of course, not talking about the largest extinctions like the Great Permian).

Some of them coincide with the falls of large asteroids, large-scale volcanic eruptions and the like, which, according to many experts, can cause mass extinctions, or at least intensify them. The idea of a cyclical mass extinction is not new, but it remains controversial.

In addition, existing studies were mainly concerned with marine organisms and showed that the cyclicality is present and ranges from 26.4 to 27.3 million years over the past 260 million years. To test this hypothesis on land animals, American experts conducted their own research.

Using the Stoters and Lutz circular spectral method, as well as other innovative mathematical models, the scientists concluded that extinction cycles also exist for terrestrial animals. But the most interesting thing is that the periodicity is also typical for global cataclysms like asteroid or comet impacts.

Thus, the impacts of large bodies on the Earth, according to the calculations of astrophysicists, occur approximately every 26-30 million years. The fact is that the solar system passes through the middle plane of the Milky Way, full of dangerous asteroids and comets, approximately every 30 million years (interaction with dark matter in this part of the Galaxy, according to the predictions of astrophysicists, can also cause cataclysms associated with volcanic activity) …

Approximately such a cycle, according to American scientists, is also the case for mass extinctions - about 27.5 million years. In any case, for three of these extinctions that have occurred over the past 250 million years, the influence of extraterrestrial objects is known, scientists note. They also emphasize that these findings require more research.

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