Scientists unlock menu of the Earth's early lifeforms

Recently discovered in southern Namibia, new fossil data on the ancient lifeform Ernietta allows scientists to understand how they ate together, and why.

JUNE 24, 2019 14:04

Fagus Sylvatica, from the Piacenzian period (photo credit: DIDIER DESCOUENS/WIKIMEDIA COMMONS) — Fagus Sylvatica, from the Piacenzian period

(photo credit: DIDIER DESCOUENS/WIKIMEDIA COMMONS)

How did the planet look 571 million years ago? Well, the short answer is, very different then the world we know today.

The emphasis here is on the word "today," since during the long process of evolution, many life-forms simply failed to adapt and therefore faded away, which means that no current life-form is around to remind us of how they looked or behaved.

Indeed, one of the reasons evolution is so difficult to fully appreciate is that it takes place over such a massive, almost cosmic, scale of time that humans have a hard time imagining without help.

One group of such life-forms that no longer exists is Ediacara biota. Named after the Ediacara Hills in South Australia where traces of them were found, delicate “prints in stone” show the remains of what once existed on this planet. Ernietta, a sack-like life form, was one member of that group.

Such fossils were also found in Namibia near the villiage of Bethanie, which is why they are called Nama-type, Haaretz reported.

Vanderbilt scientists Simon A.F Darroch and Beandt M. Gibson used these findings, which were returned to Namibia, to reach a startling conclusion about Ediacara biota.

Group life, and ergo eating in groups to sustain life, began much earlier than previously thought.

The Namibia findings pre-date the Cambrian explosion by roughly 30 million years, give or take a few millions.

The explosion was in the variety and complexity of life forms that began to appear on earth. It is named after Cambria (Wales in Latin), where some sites best illustrate it.

Hence, it is possible that our understanding of when complex life-forms began to act socially on Earth needs to be tweaked; it might have been much earlier than we thought.

Using computers to create fluid dynamics simulations, Darroch and Gibson were able to demonstrate how colonies of Ernietta floated together to enjoy nutrients delivered by the ancient sea currents - and even emptied themselves away from the feeding site.

The study, called “Gregarious suspension feeding in a modular Ediacaran organism,” was published in Science Advances, Vanderbilt News reported.

“They were enhancing the amount of nutrients going from individual to individual, and they were also exporting waste down-current and away from the one making it,” Gibson said.

“So it was a good dinner party , in that they got to eat a lot and didn’t have to sit in their own waste.”

“They are behaving like animals, and that’s a link between them and what we recognize as animals,” Darroch said.