Science

1.4-million-year-old footprints in Kenya indicate larger body size for early human relative

Fossilized tracks near Lake Turkana suggest Paranthropus boisei reached human-like sizes and lived in complex social groups.

Updated Aug 30, 2026 · 16:20 UTC1 reports

The short version

A newly analyzed fossil footprint trail near Kenya's Lake Turkana reveals eight Paranthropus boisei individuals who appear to have traveled together 1.4 million years ago.
Measurements of the tracks indicate some individuals reached up to 1.8 meters in height and 75 kilograms in weight, challenging previous assumptions that the species was much smaller than Homo erectus.
Researchers identified most of the trackmakers as adult males, suggesting a complex social structure where males tolerated one another for protection.
The international research team plans to return to Kenya to continue investigating lake margin footprint sites across the region.

Fossilized footprint trails near Lake Turkana in northern Kenya record eight Paranthropus boisei individuals occupying the same location around 1.4 million years ago.[ScienceDaily]
Footprint size analysis suggests some of the individuals reached heights up to 1.8 meters and weights around 75 kilograms.[ScienceDaily]
The trackmakers were determined to be mostly adult males, with no clear evidence of females or children present in the group.[ScienceDaily]
The study involved scientists from Chatham University, Harvard University, the Max Planck Institute for Evolutionary Anthropology, the Smithsonian Institution, and the National Museums of Kenya, and was published in the Proceedings of the National Academy of Sciences.[ScienceDaily]

Researchers are still investigating the precise geological conditions that allowed the footprints to be preserved over more than 100,000 years along the ancient lakeshore.[ScienceDaily]