For many years, biologists assumed that the emergence of complex life was an evolutionary inevitability. Once simple life emerged, it gradually evolved into more complex forms, eventually giving ...

Roughly 1.5. billion years earlier than scientists believed complex life on Earth could have existed. However, the theory also says that the organisms were still very simple and that they were ...

A team of international researchers has challenged the long-held belief that complex life forms first emerged on Earth 635 million years ago, presenting findings that show life may have existed ...

"This would have provided sufficient energy to promote increases in body size and greater complex behavior observed in primitive, simple animal-like life forms such as those found in the fossils ...