Experts have not found confirmation of the hypothesis that mammoths inhabiting North America were destroyed when a meteorite or comet fell to Earth 13 thousand years ago. Scientists were looking for traces of the fall of a celestial body in the sediments of that time, but they were unable to find anything. The researchers published their findings in the journal Proceedings of the National Academy of Sciences. The ScienceNOW portal writes briefly about the work
The assumption that woolly mammoths and other representatives of megafauna became extinct due to the fall of a celestial body on the planet 12.9 thousand years ago, was put forward in an article in the Proceedings of the National Academy of Sciences, published in 2007. Animal populations, according to scientists, were destroyed due to the forest fires that began after the fall, which affected the entire continent.
Such a large-scale disaster should have left many traces. So, a comet or an asteroid would bring the metal iridium with them to the Earth, in addition, as a result of the fall, magnetic microspheres and granules of a certain mineral composition should have formed. Another proof of a large celestial body falling to the planet would be nanodiamonds, which can only form at very high pressure and temperature during impact.
The authors of the new work and several previous studies have tried to find any of these traces, but all attempts have failed. In particular, the researchers showed that microspheres are present in rocks dating back not only to the time period about 12.9 thousand years ago, and there is no significant increase in concentration in the layers corresponding to the alleged collision. As for nanodiamonds, the authors of the new work note that in previous studies, other forms of carbon were probably taken for them.
Scientists who have published earlier work in which the validity of the hypothesis of the collision of the Earth with a celestial body 12.9 thousand years ago was proved, stated that they were not convinced by the findings of the latest study. In particular, according to experts, they did not confuse different forms of carbon with each other.
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New evidence has emerged in favor of the theory of massive bombardment of the Earth by meteorites, which caused the extinction of the dinosaurs, reports the journal Geology
In the scientific world, they do not get tired of defending their innocence, both supporters of a global cataclysm, which led to the extinction of prehistoric animals, and their opponents. This time the balance tipped in favor of the former. The reason for this is the find that was made in Ukraine in the vicinity of Kirovograd. Recall that earlier scientists have designated here the place of the meteorite fall, the scattering zone of which included not only Central Ukraine, but also Romania, Crimea, Russia.
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The studies, which were conducted by Ukrainian scientists from the Institute of Geological Sciences of Ukraine with the participation of British researcher David Jolly from the University of Aberdeen, were aimed at studying pollen and spores of fossil plants in the Boltysh crater.
In addition to ferns, which were the fastest to settle on the lands devastated after the meteorite fell, scientists were able to find another fossil layer, which, as suggested by one of the authors of the study, an employee of the Open University in Great Britain, Simon Kelly, was formed after a meteorite fell on the Yucatan Peninsula.
Simon Kelly's colleague, Monica Grady, who specializes in meteorites, hypothesized that the bombing could have been the result of a collision of two large space objects in near-Earth space.
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