Dhaka, Oct. 4 -- The first animals may have appeared hundreds of millions of years earlier than their oldest known fossils, according to a new modelling study.

The research team has suggested that animals could have emerged between 800 million and 700 million years ago, roughly 200 million years earlier than the fossil record indicates. The study was published Friday in Science Advances.

The earliest undisputed animal fossils date to about 574 million years ago, during the Ediacaran period. But the researchers argue that the patchy fossil record cannot by itself establish when animals first evolved.

Where Are the Animals?

According to Live Science, researchers studied more than 140 samples from the Kheseen Biota in Mongolia, a deposit...