Expert: Ralph Salier - 10/16/2008

Question
Hello Ralph,

I'm just a layman interested in our journey as a species spreading from Africa to the rest of the world. All of major land-mass invasions by our ancestors were done on foot. Even it was due to the existence of Beringia that the ancestors of Native Americans were able to cross from Northeast Asia.

My special interest is in the peopling of Australia. There's evidence that 50 thousand years ago, our species has arrived in Australia. The fact is that at that time, more than 50 miles of open ocean existed between southwestern-most tip or Timor Island and Australia, which means they had to be crossing some open waters. Was this possible? I mean at a distance of 50 miles, you will never know whether some land exists beyond the horizon. Moreover, did they have the navigational skills? If the invention of wheels only happened several thousand years ago, how came the ancestor of Australian Aborigines know how to sail tens of thousands of years ago? We are not marine mammal, are we?

Is this possible that actually no water barrier existed during the crossing from Asia to Australia? That actually there existed a kind of land bridge stretching from Sumatra all the way down to Arnhem land?

Thanks for your answer.

Best Regards

Indro Cahyono
Jakarta, Indonesia

Answer
Hi Indro,

During the various glaciations, the water levels of the oceans were much lower then they are today.  During some of these low water periods, the distance from Borneo to Northern Australia was much narrower and one could see across the straits.  In addition, between 40 and 50 thousand years ago and perhaps even before this, humans had the knowledge of building water craft.  Some may even have allowed  the early Polynesians move to some of the islands such as the Phillipines and Japan.  How far they could have traveled is a matter of conjecture.  Some say that those ancient navigators may have reached the Americas.  It is also possible that the Native Americans may have come from Europe along the edge of the ice in boats!  Now as an archaeologist I'd like to see proof of this but none has been found as yet.  

But I would say that the navigations skills of the ancient ones was truely amazing and if you consider that the Pacific Ocean was fully peopled by these brave navigators, It would not surprize me that the ancient aboriginies got to Australia during their mythical dream time.

I hope that I answered your question.

By the way, the Aborigines, Kung San Bushmen of the Kalihari desert of South Africa and one of the tribes of southern Indians are most closely related genetically from the rest of the human population indicating that at one time these widely dispursed peoples may have traveled by sea.