Researchers Discover Possible Cause of the First Mass Extinction on Earth

Researchers from the Vanderbilt University have discovered new fossil evidence showing that the emergence of newly evolved biological organism, called "ecological engineers", has contributed to the first mass extinction that occurred on Earth 540 million years ago.

Their findings, published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology, revealed that the newly discovered fossils showed the unusual transitional ecosystem that existed before the Cambrian Explosion, suggesting an overlapping ecological association between metazoans and soft-bodied Ediacaran organisms.

Ediacarans were the first multi-cellular organisms that evolved and filled the Earth around 600 million years ago. After 60 million years, the first animals called metazoans was given birth. Unlike Ediacarans, metazoans are capable of moving spontaneously and independently. These newly evolved organisms sustain themselves by eating other organisms or what other organisms produce. For about 25 million years, the metazoans underwent a frenzy of diversification called as the Cambrian Explosion, which is considered to be the origin of most of the modern animal families, including vertebrates, mollusks, arthropods, annelids, sponges and jellyfish.

"These new species were 'ecological engineers' who changed the environment in ways that made it more and more difficult for the Ediacarans to survive," explained, Simon Darroch, assistant professor of earth and environmental sciences at Vanderbilt University and director of the study, in a statement.

The researchers observed that some of the burrow fossils they have discovered are usually interpreted as being formed by sea anemones, which are passive predators that may have preyed upon Ediacaran larvae. Additionally, researchers found animal fossils preserved in place at the base of Ediacaran frondose organisms' strands.

Darroch believe that their findings, even though occurred 540 million years ago can be relevant in modern times.

"The end-Ediacaran extinction shows that the evolution of new behaviors can fundamentally change the entire planet," said Durroch in a press release. "And today we humans are the most powerful 'ecosystems engineers' ever known."