1.5 million year old footprints reveal key moment in human evolution

More than a million years ago, there was a hot savanna absolutely teeming with wildlife. It sat near the shore of what is now known as Lake Turkana in Kenya. It’s notable because two completely different species of hominins may have passed each other as they scavenged for food. And now, for the first time ever, researchers have a fossilised example of them living side-by-side. But what does this mean, exactly? (Picture: Kevin Hatala/Chatham University)

Hominins is a new term that describes a subdivision of the larger category known as hominids. What are hominids? Well, they are all organisms, extinct or alive, that are considered to be within the human lineage that emerged after the split from the ancestors of the great apes, roughly 6 or 7 million years ago (Picture: Louise N. Leakey/Rutgers )

But now scientists have finally examined 1.5-million-year-old fossils they unearthed. They have come to the conclusion that the fossils represent the first example of two sets of hominin footprints made about the same time on an ancient lake shore. And this finding offers hard proof that different hominin species lived simultaneously in time and space, as they evaded predators and tried to survive the ancient African landscape (Picture: Neil Roach)

Professor Kevin Hatala has been investigating hominin footprints for over a decade and is the first author of an associated study published in the journal Science. He said: ‘Fossil footprints are exciting because they provide vivid snapshots that bring our fossil relatives to life. With these kinds of data, we can see how living individuals, millions of years ago, were moving around their environments and potentially interacting with each other, or even with other animals. That’s something that we can’t really get from bones or stone tools’ (Picture: Kevin Hatala/Chatham University)

It’s thought that if the two species, which were the more human-like Homo erectus and the more ape-like Paranthropus boisei, didn’t cross paths then they would have traversed the area within just hours of each other, Rutgers University’s Professor Craig Feibel said. He was a co-author of the study and has conducted research in that area since 1981 (Picture: Getty)

The fossils were first found in 2021 alongside fossil bones. Then the prints were distinguished using a three-dimensional analysis, revealing different patterns of anatomy and movement. But it was a year later, in July 2022, where the footprint surface was excavated. It’s been long hypothesised the hominins coexisted, but their fates were different. Homo erectus, a direct ancestor of humans, lasted for a million more years, while Paranthropus boisei went extinct within the next few hundred thousand years (Picture: Kevin Hatala/Chatham University)

The reason why remains a mystery, as both species were bipedal, agile, and had upright postures. Professor Feibel noted that the trace fossils cannot be moved unlike bones and other body fossils. He said: ‘This proves beyond any question that not only one but two different hominins were walking on the same surface, literally within hours of each other. The idea that they lived contemporaneously may not be a surprise. But this is the first time demonstrating it. I think that’s really huge’ (Picture: Craig Feibel)