Big Mouth, No Butt: Oldest Human Ancestor Found?

Researchers have found what they believe to be the earliest known prehistoric ancestor of humans, and it looks scary and ancient as you can imagine.

The species was identified from microfossils found in limestones is China. It was named Saccorhytus coronarius because of its sack-like appearance.

UPI notes that the species is among the first deuterostomes, which spawned a variety of sub-groups, including vertebrates. It has lived approximately 540 million years ago.

Simon Conway Morris, Professor of Evolutionary Palaeobiology and a Fellow of St John's College, University of Cambridge, said in a statement: "We think that as an early deuterostome this may represent the primitive beginnings of a very diverse range of species, including ourselves. To the naked eye, the fossils we studied look like tiny black grains, but under the microscope the level of detail is jaw-dropping. All deuterostomes had a common ancestor, and we think that is what we are looking at here."

Degan Shu, from Northwest University, added, " Saccorhytus now gives us remarkable insights into the very first stages of the evolution of a group that led to the fish, and ultimately, to us."

The study, which was published in journal Nature, describes Saccorhytus coronaries as about a millimeter in size and probably lived between grains of sand on the seabed. Science Alert further notes that the species had a huge mouth, which allowed it to eat large prey and was covered with thin skin and muscles so it could fit itself easily on the seabed.

There was no clear indication the animal had an anus. Rather, it was suspected that it expelled water and waste through its features that resemble eyes and nostrils.

The researchers had to examine about three tons of limestones to get the fossil that would allow them to replicate the appearance of Saccorhytus coronaries.

The study was carried out by researchers from the University of Cambridge in the U.K. and Northwest University in Xi'an China, with support from other colleagues at institutions in China and Germany.