Evidence gathered from recent researchers confirms that animals caused the first mass extinction event that took place on our planet 540 million years ago. Scientists had, till this evidence came along, attributed the catastrophe to a meteorite impact or massive volcanic eruption but they now have reasons to believe that it was caused instead by the rise of early animals who changed the prehistoric environment on the surface of this planet dramatically.
Researchers at the Vanderbilt University study points to the evolution of early animals as the real cause now.
Certain vertebrates, which were among the first animals to appear on Earth, like molluscs and jellyfish, ate up all the Ediacarans who had co-existed peacefully for nearly 60 million years before this calamity befell them.
Assistant Professor of Earth and Environmental Science at Vanderbilt University in the US – Simon Darroch said, “People have been slow to recognize that biological organisms can also drive mass extinction.”
The earliest inhabitants of our planet were unicellular organisms. For 3 billion years, they reigned supreme here. Animals came into being several billion years later after a long drawn process of evolution.
Most present day animal families including vertebrates, molluscs, arthropods, annelids, sponges and jellyfish appeared during the 25 million year period of Cambrian explosion.
In this case, researchers analyzed the youngest known Ediacaran community that existed in Namibia nearly 545 million years ago.
Darroch also said that the diversity of species at this site was much lower, and there was evidence of greater ecological stress than at comparable sites that are 10 to 15 million years older.
After careful analysis, the team is now convinced that the first mass extinction was triggered off by a combination of various factors, mainly ecological stress, biological interactions and ecosystem engineering.