Neanderthals were ancient mariners

Neanderthals may have beaten modern humans to the seas. Growing evidence suggests our extinct cousins criss-crossed the Mediterranean in boats from 100,000 years ago, although not everyone is convinced they weren't just good swimmers.

Neanderthals lived around the Mediterranean from 300,000 years ago. 

Their distinctive "Mousterian" stone tools are found on the Greek mainland and, intriguingly, have also been found on the Greek islands of Lefkada, Kefalonia and Zakynthos. 

That could be explained in two ways: either the islands weren't islands at the time, or our distant cousins crossed the water somehow.

Now, George Ferentinos of the University of Patras in Greece says we can rule out the former. The islands, he says, have been cut off from the mainland for as long as the tools have been on them.

Ferentinos compiled data that showed sea levels were 120 metres lower 100,000 years ago, because water was locked up in Earth's larger ice caps. 

But the seabed off Greece today drops down to around 300 metres, meaning that when Neanderthals were in the region, the sea would have been at least 180 metres deep (Journal of Archaeological Science, DOI: 10.1016/j.jas.2012.01.032).