Fossilised primate jaw discovery sheds new light on human evolution

28 Feb 2017

Human jawbone. Image: sruilk/Shutterstock

The tree of human evolution is still missing a few branches, but the new discovery of a fossilised primate jaw offers us some fresh clues.

We all know that we descended from primates, but beyond that, some holes exist in the knowledge of our origins (bar a weird, sack-like sea creature with no anus).

Now however, a group of palaeontologists and evolutionary biologists have unearthed a specimen that is helping us figure out a bit more about where we come from.

The specimen, unearthed by researchers from the University of Southern California, was found after six years of digging in the Kashmir area in northern India.

After being analysed, the fragmented jaw was found to belong to an entirely new species of primate called Ramadapis sahnii, which existed between 11 and 14m years ago.

A member of the ancient Sivaladapidae primate family, the Ramadapis sahnii would have been a herbivore, roughly the size of a domestic cat today.

In a paper published in the Journal of Evolution, the researchers said this was the first discovery of a new primate species in nearly 40 years in the area, and it is believed to have outlived its cousins in other parts of the world by millions of years.

This begs the question: what conditions existed in the Kashmir region that prevented the species from going extinct?

Fossil jaw

The jaw from the newly discovered Ramadapis sahnii species that existed between 11 and 14m years ago. Image: Sheena Lad

A need to understand all primate origins

The discovery of this specimen marks a change of thinking in the field of palaeontology, as co-author Biren Patel admitted that fossil hunters of the past were more focused on the search for big finds, or ones “they could show off to other people”.

This discovery fills an ecological and biogeographical gap that has been largely misunderstood or unknown in Asia.

“People want to know about human origins, but to fully understand human origins, you need to understand all of primate origins, including the lemurs and these Sivaladapids,” Patel said. “Lemurs and sivaladapids are sister groups to what we are – the anthropoids – and we are all primates.”

Colm Gorey was a senior journalist with Silicon Republic