Saturday, February 8, 2014

Hominin Footprints in England

As I half-watched, half-listened to the news last evening, my attention was drawn to a report that "human footprints" had been found in England, dating from almost 1 million years ago.  Of course, I knew that this could not be true since we humans did not evolve in Africa until 130,000 years ago and did not reach Europe until about 40,000 years ago.  The footprints thus predate humans, Homo sapiens, by at least 700,000 years.

In fact, the footprints, discovered last May on a beach in Norfolk, England, are thought to be those of Homo antecessor, a hominin that lived from about 1 million years ago to 600,000 years ago; fossils of this early hominin were found in Spain in 2007.  The footprints, preserved in compacted mud and thought to be about 900,000 years old, appear to have been left behind by two adults and three children as they foraged along an estuary.  A warm interglacial period of the Pleistocene, preceding the Wisconsin Glaciation, allowed these nomadic hominins to wander farther north than had previously been documented; at that time, England was contiguous with France (i.e. the English Channel did not exist).

While the complex lineages of the Homo genus remain uncertain, it is certainly wrong to refer to these footprints as being "human."  Homo erectus had evolved in Africa about two million years ago and spread from that Continent within 200,000 years, moving eastward toward Southeast Asia (they were the first hominins known to leave Africa).  Neanderthals and Denisovans arose in Africa about 350,000 years ago, having split from a common ancestor that evolved about 650,000 years ago; Neanderthals did not reach Europe until 300,000 years ago (300,000 years after Homo antecessor had become extinct) and disappeared about 30,000 years ago as humans colonized the continent.  The footprints in Norfolk, England are fascinating clues to the puzzle of hominin evolution but they were certainly not produced by humans.