The increase in oxygen concentration in the Earth's atmosphere more than 400 million years ago contributed to an explosive growth in the number of living organisms. This conclusion was reached by a group of scientists led by David Fike (David Fike) from the University of Washington. This was announced in a press release on the Phys.org website.
The researchers analyzed carbonate rocks that formed during the Middle and Late Ordovician period (485-443 million years ago). Geologists found that there was an almost 80 percent increase in oxygen levels during this interval. Before that, its share in the air was 14 percent, after - 24 percent.
Around this time - just over 445 million years ago - biodiversity increased threefold. This explosive growth is called the Great Ordovician Biodiversification.
According to scientists, the results show that after the Cambrian explosion, the oxygen content remained low and reached modern values only after several tens of millions of years. The rise in oxygen levels in the ocean has led to the emergence of new species of living organisms.
The Cambrian Explosion is another biodiversity explosion. During it (about 540 million years ago) the main types of modern animals arose.