The scientists discovered a catastrophic trigger in ancient fossils that may point to the cause of the largest extinction of living organisms on the Earth. It is called the Permian-Triassic, or Great Extinction, and it happened about 250 million years ago. The study that gave the scientists new conclusions, was carried out on the basis of the study of fossilized shells of molluscs in the territory of the modern Southern Alps.
Their peculiarity lies in the fact that they are able to fix the pH level of the Sea water. It, in turn, is influenced by the concentration of carbon dioxide in the atmospheric air. Their values in the fossilized remains indicate that about 252 million years ago there was a sudden and intense release of a huge amount of CO2 into the planet's atmosphere.
The rise in carbon dioxide levels could be caused by a series of volcanic eruptions located in modern Siberia. It could lead to significant warming and sharp acidification of the water in the ocean, it was the result of the death of some species of plants and animals in a very short period.
But in parallel, the ocean depths became rich in nutrients, which over a long period led to the depletion of the oxygen level in the water and the further extinction of living organisms in the water.
A biochemist Hana Yurikova from the University of St Andrews believes that this domino effect of interconnected important cycles has led to a catastrophic mass extinction.
By studying the isotopes of boron and carbon in the shell, the scientists concluded that the Great Extinction was preceded by a powerful greenhouse effect that emerged as a result of the prevailing circumstances.
Knowledge of what happened millions years ago on our planet allows the scientists to make predictions about the situation on the Earth in the near future.