Mass extinction of animals on Earth that happened 444 million years ago on the border of the Ordovician and Silurian periods were triggered by a sharp decrease in the concentration of oxygen in the atmosphere and oceans. To such conclusion scientists from the USA, the UK and the Czech Republic, published the results of a study in the journal Nature Communication.
Scientists have discovered ancient fossils of Libya, after the isotope study which confirmed a sharp decline in oxygen concentration at the border of the Ordovician and Silurian periods.
According to scientists, due to the fall in oxygen in the ocean to almost zero became extinct about 85% of marine invertebrates.
As scientists have found that such oxygen-free era lasted about three million years. In his article, the researchers not known the reasons why it rapidly disappeared, the oxygen of earth’s atmosphere and ocean.
