The footprints were left in the mud by two different species “within a matter of hours, or at most days,” a co-author of the research study said.

Muddy footprints found beside Lake Turkana, Kenya reveal two ancient hominin species were once neighbors 1.5 million years ago.

Researchers discovered 1.5-million-year-old footprints in Kenya's Turkana Basin, revealing coexistence of Paranthropus boisei and Homo erectus. The prints, showing distinct walking patterns, provide direct evidence of the two species' interaction and environment,