footprints from Trachilos

Credit: Andrzej Boczarowski (1st author of the study)

Most paleontological evidence suggests early humans evolved and diverged from their ape ancestors in southern and eastern Africa, remaining on the continent for several million years before migrating to Europe and Asia. Supporting this idea, last year research was presented on a discovery of footprints made by an early human ancestor more than 3.6 million years ago.  The discovery occurred in Tanzania, Africa,  and was made when some of our distant relatives, known as Australopithecus afarensis walked together across wet volcanic ash.  The tracks were considered the oldest prints of their kind ever found.  Lucy, a young adult female who lived in Ethiopia 3.2 million years ago, is perhaps the most famous example of Australopithecus afarensis.  Most everything about this discovery seemed to tie the story and timeline of human evolution and divergence originating in Africa.  But paleontologists have just announced finding 5.7 million-year-old, unmistakably human-like footprints in Trachilos, Crete, clouding the narrative of human evolution.

The prints found in Crete exhibit a human-like big toe and the ball shape distinctively found on the sole of human feet. Until recently, no hominin fossils older than 1.8 million years had been discovered outside of Africa. Per Ahlberg, a paleontologist at Uppsala, University summarized the finding in a news release: “What makes this controversial is the age and location of the prints.” The research published in the Proceedings of the Geologist Association, states the footprints were dated using a combination of fossilized marine microorganisms called foraminifera and the character of the local sedimentary rocks.  The press release points out that at the time when the Trachilos footprints were made, (known as period known as the late Miocene) savannah-like environments extended from North Africa up around the eastern Mediterranean. Furthermore, in the late Micene period the now island of Crete was still attached to the Greek mainland. This leaves the possibility that early hominins could have ranged across south-east Europe as well as Africa.  “This discovery challenges the established narrative of early human evolution head-on and is likely to generate a lot of debate. Whether the human origins research community will accept fossil footprints as conclusive evidence of the presence of hominins in the Miocene of Crete remains to be seen,” says Per Ahlberg.