In the south of Australia, researchers discovered the dwellings, and then the remains of the creatures themselves, which they called the oldest animals on the planet. Their scientific name is Ikaria wariootia, and they looked like tiny worms. These creatures lived at the very end of the Ediacaran era, at a time when life had just got out of the water onto land.
First, scientists found a rock, dotted with traces of tunnels, paved by unknown creatures. They established this fact by the characteristic marks on the walls of the tunnels. And then on a nearby boulder was found a fair amount of fossil remains of Ikaria wariootia themselves, which were identified using a three-dimensional laser scanner.
Result of laser scanning of the remains of Ikaria
The size of the worm was small, 2–7 mm in length and 1, 2–1, 5 mm in width. The age of the remains is approximately 555 million years. In the fossils, a two-sided structure is imprinted extremely accurately, in which one extremity of the body is the mouth, and the other removes waste. In the middle is an extremely primitive, but functional digestive system. This two-sided structure has survived for hundreds of millions of years and has been inherited by millions of animal species.
In fact, given its age and structure, scientists tend to consider Ikaria wariootia the most ancient ancestor of all terrestrial animals, which include dinosaurs, insects and mammals. The rather complex structure of the body and traces of vigorous activity make it possible to unambiguously separate this species from the inhabitants of the ancient oceans. Thus, Ikaria wariootia also became the first land creature known to us today.
Tunnels in stone, eaten by Ikaria wariootia