Scientists have discovered when the land was covered with the first plants
MOSCOW, 19 Jul — RIA Novosti. Paleontologists from the UK found evidence that the first land plants appeared on Earth approximately 500 million years ago, that is, a hundred million years earlier than was given the previous calculations, according to a paper published in the journal PNAS.
“The emergence of plants on the Earth’s surface radically altered its climate and appearance, greatly accelerating the erosion of soil and rocks and dramatically reducing the amount of greenhouse gases in the atmosphere that led to the cold climate and other changes. We showed that it occurred in the middle Cambrian period, at the same time, when the first land animals,” says Jennifer Morris of the University of Bristol (UK).
Today scientists believe, the first trees appeared in the middle Devonian period, about 400 million years ago. Their appearance has drastically changed the face of the planet, making it “green” by filling its atmosphere a huge amount of oxygen and giving rise to many new species of animals, including ground insects and fungi that feed exclusively on plant biomass.
What looked like these first trees, remains a mystery for paleontologists — it is known only a small number of “petrified forest”, a special type of deposits that time, which preserved the full trunks and root systems of these trees trapped underground due to volcanic ash or lava. Their study shows that it was a very bizarre objects, in which the role of the leaves played a special photosynthetic bark, and in appearance they resembled modern dwarf trees of the tundra.