An article published in the journal “Science Advances” describes a computer simulation carried out to better understand how to eat the Tribrachidium Heraldicum (photo ©Aleksey Nagovitsyn), a creature that lived about 555 million years ago. The results reveal that in such an ancient time there was already a complex ecosystem formed by the first complex organisms greater than previously thought.

The Tribrachidium is still a rather mysterious creature that lived during the Ediacaran period, between 635 and 542 million years ago. Fossils of this sea creature with a length between 3 mm and 5 cm were found for the first time in the Ediacaran of South Australia, the region that gives its name to the period and later in Canada and Russia.

The Ediacaran period came before the Cambrian explosion, where there was a huge diversification of life forms. The first fossils of what is called Ediacaran fauna, or Ediacaran biota, were found in the late 19th century but they’re organisms so different from the present ones that it’s difficult to understand whether their ancestors of the subsequent ones or they form one or even more phyla now extinct. According to some interpretations they’re not even animals.

The difference between the Tribrachidium and present animals can be seen immediately by its triradial symmetry, unknown in phyla existing today. For this reason, it was difficult for paleontologists to understand how this creature lived. A team of scientists has used a fluid dynamics simulation to understand how it fed.

This computer technique is used for example in the field of engineering to study the aerodynamics of airplanes or buildings, but only recently was applied for the first time in the field of paleontology. It may seem a curious application but simulating the flow of water around a virtual model of Tribrachidium helped to understand how it fed.

The study showed that the Tribrachidium was a so-called suspension feeder, which means that it fed of something floating on water remaining suspended in it. It’s a way of feeding that until now was unknown in such ancient organisms revealing a complexity greater than previously known. The application of a computer technology previously used in completely different fields is also helping paleontologists finally understand organisms that are very ancient and very different from the current ones.