New York, April 11 (IANS): In what could pave way for new interpretation of evolutionary history, researchers have now uncovered rare 500-million-years-old fossilised embryos of unknown organisms.

The fossilised embryos the researchers found were significantly smaller than other fossil embryos from the same time period, suggesting they represent a yet undescribed organism.

“Before the Ediacaran and Cambrian Periods, organisms were unicellular and simple,” said James Schiffbauer, assistant professor of geological sciences at University of Missouri.
The Cambrian Period, which occurred between 540 million and 485 million years ago, ushered in the advent of shells.

Over time, shells and exoskeletons can be fossilised, giving scientists clues into how organisms existed millions of years ago. This adaptation provided protection and structural integrity for organisms.

“My work focuses on those harder-to-find, soft-tissue organisms that weren’t preserved quite as easily and aren’t quite as plentiful,” Schiffbauer said.

It is important to understand how the fossils were preserved, because their chemical makeup can also offer clues about the nature of the organisms’ original tissues, Schiffbauer said.

Additional research will focus on identifying the parents of these embryos, and their evolutionary position.

The study appeared in the Journal of Paleontology.