Life 800 million years ago was much more diverse than believed

About 800 million years ago, before the supercontinent Pangea formed, life on Earth was more diverse than commonly accepted theory maintains, according to a surprising new study. The new study indicates that at that time, the Neoproterozoic era, different lineages of amoebas and ancestors of plants, algae and animals were already established and survived the two glaciations that covered the entire planet in ice.

The study is the work of a team led by Alfredo L. Porfirio-Sousa of the University of Sao Paulo in Brazil.

The classic paradigm of the Neoproterozoic era was that there was virtually no life on the planet, apart from a few species of bacteria and protists. In the last 15 years, however, fossils of unicellular, eukaryotic and heterotrophic organisms have been identified in different places around the world. These fossils date back to about 800 million years ago.

The new study focused on the origin and divergence times of amoebozoans, showing that many of these organisms, as well as ancestors of plants, algae, fungi and animals, even survived the two glaciations of the Cryogenic period (between 790 million years ago). years and 635 million), the second period of the Neoproterozoic era, preceded by the Tonic period and followed by the Ediacaran. It is believed that polar ice spread to cover the entire planet for about 100 million years in this period.

The study has allowed us to date the massive diversification of life on Earth about 260 million years earlier than previously believed, long before the Cambrian explosion (the appearance of many new multicellular organisms at the beginning of the Cambrian period, between 541 million years ago). and 530 million). During this period, which enjoyed a warm and humid climate, the Earth was mainly inhabited by marine invertebrates such as trilobites, brachiopods and graptolites.

Fossil of a living being from between 720 million and 635 million years ago. (Image: Luana Morais and João Alcino)

The study is titled “Amoebozoan testate amoebae illuminates the diversity of heterotrophs and the complexity of ecosystems throughout geological time.” And it has been published in the academic journal Proceedings of the National Academy of Sciences (PNAS). (Fountain: NCYT by Amazings)