Suffolk Reporter

The Koobi Fora Research Project team, led by Louise Leakey, has been conducting paleoanthropological research at Lake Turkana in Kenya for many years. Leakey, a research professor at Stony Brook University and the Turkana Basin Institute, along with an international team of researchers from Kenya, the United States, and the UK, co-authored a new study published in Science. The study presents a ~1.5-million-year-old fossil footprint site in northern Kenya that records two distinct types of ancient human footprints, indicating different anatomical and locomotion patterns.

Traditionally, the paleontological record has not been sufficient to determine whether fossil human species lived together on the same landscapes at the same times. However, researchers were able to differentiate between the two types of footprints using newly developed 3D analysis methods.

The fossil footprints were discovered in 2021 when Leakey and Cyprian Nyete were excavating unassociated hominin skeletal fossils. Richard Loki was part of that excavation team and identified the first hominin footprint. Subsequently, Leakey coordinated a team led by Kevin Hatala from Chatham University to excavate the footprint surface in July 2022.

“Fossil footprints provide us a clear picture of that instant in time, 1.5 million years ago,” said Leakey. “The different human ancestors may well have passed by each other and observed the giant stork, ancient horses and hippos that also left their footprints along that shoreline that day.”

This study offers direct evidence of two different fossil human relatives — Homo erectus and Paranthropus boisei — sharing the same landscape and possibly interacting with each other. While skeletal fossils have traditionally been used to study human evolution, data from these fossil footprints are revealing more about human anatomy evolution and providing insights into ancient behaviors and environments.

“Documenting the strata revealed that there are many more trackway surfaces that could be excavated nearby,” said Kay Behrensmeyer from the Smithsonian’s National Museum of Natural History. “These might hold more clues that could address questions about how different hominin species interacted.”

Around 1.5 million years ago in Kenya's Turkana Basin, it is hypothesized these fossil human species coexisted together. Homo erectus is considered a possible direct ancestor of modern humans while Paranthropus boisei went extinct within a few hundred thousand years after this period.

The research received support from organizations including the National Geographic Society, U.S. National Science Foundation, Turkana Basin Institute, and UK Research and Innovation.