During the first four billion of its existence, our planet was devoid of any life, except microbes. The situation changed radically at the moment when the Earth began to green plants, which created a favorable environment for the colonization of the continents by animals. Previously, scientists believed that it happened about 420 million years ago, based on the recovered fossils fossil plants. But new findings have forced them to change their minds.
A new study published in the journal Proceedings of the National Academy of Sciences (“Proceedings of the National Academy of Sciences”), argue that the colonization of the surface of the Land by plants occurred at 100 000 000 years earlier than was supposed before. And it seriously changes the perception science of the evolution of the biosphere of our planet. After all, plants are one of the key factors in the carbon cycle, regulating the atmosphere and climate of the planet for hundreds of millions of years.
A team of researchers from the School of Earth Sciences at Bristol University used a technology called “molecular clock” method of Dating phylogenetic events based on the hypothesis that evolutionary significant replacement of monomers in nucleic acids or amino acids in proteins occur with almost constant speed. Thus scientists it became clear that the first land plants existed on the Earth in the middle of the Cambrian period, which started 541 million years ago.
“The global spread of plants and their adaptation to life on land has led to an increase in indicators of continental weathering (the process of destruction and chemical changes of rocks). All this eventually led to a sharp decrease in the level of carbon dioxide in the atmosphere and to global cooling. Previous attempts to simulate these changes in the atmosphere turned out to be inaccurate. Our research is making some adjustments to the already existing model of the evolution of the biosphere”, — shares his thoughts the author of the study Dr. Jennifer Morris.