Posthuman Blues

Study treads on footprint claim

If confirmed, the 40,000-year-old marks would have debunked accepted theories of human migration into the Americas.

But the ash has now been dated to 1.3 million years ago - more than a million years before modern humans evolved.

Relatives of our species living at this time were not capable of making the journey to the Americas, experts say.

Why assume the prints are human? Perhaps, if authentic, they were made by humanoid aliens or cryptohominids.