Monday, June 13, 2011

Exciting Discoveries in Dmanisi

Here is some tantalizing evidence that suggests both an earlier Out of Africa date (1.85 million vs. 1.7 mya) and a two way migration (Out of Africa to Asia and back again). Basically, this means that it is possible that our earliest ancestors developed in the Caucasus and then returned to Africa where they evolved into Homo sapiens. The evidence comes from the Dmanisi site in Georgia (the country, not the state) that has already revolutionized our ideas about Homo erectus and its march across Eurasia. From the article:

"The accumulating evidence from Eurasia is demonstrating increasingly old and primitive populations," said Reid Ferring of the University of North Texas. Dmanisi is located in the Republic of Georgia.

"The recently discovered data show that Dmanisi was occupied at the same time as, if not before, the first appearance of Homo erectus in east Africa," the team led by Ferring and David Lordkipanidze of the Georgia National Museum reported. They uncovered more than 100 stone artifacts in deep layers at the site. Previously, fossil bones from a later period had been found at the site.

The new discovery shows that the Caucasus region was inhabited by a sustained population, not just transitory colonists. "We do not know as yet what the first occupants looked like, but the implication is that they were similar to, or possibly even more primitive than, those represented by Dmanisi's fossils," Ferring explained.

The occupants of Dmanisi "are the first representatives of our own genus outside Africa, and they represent the most primitive population of the species Homo erectus known to date," added Lordkipanidze. The geographic origins of H. erectus are still unknown.

The early humans at Dmanisi "might be ancestral to all later H. erectus populations, which would suggest a Eurasian origin of H. erectus," said Lordkipanidze. However, there's another theory as well: H. erectus originated in Africa, and the Dmanisi group might represent its first migration out of Africa.

To read the article, click HERE.

Thursday, June 9, 2011

The Earth is Full

The most read story in the New York Times today is by Thomas Friedman who discusses ecological footprints to make the case that we may be reaching a tipping point with regard to the environment.
You really do have to wonder whether a few years from now we’ll look back at the first decade of the 21st century — when food prices spiked, energy prices soared, world population surged, tornados plowed through cities, floods and droughts set records, populations were displaced and governments were threatened by the confluence of it all — and ask ourselves: What were we thinking? How did we not panic when the evidence was so obvious that we’d crossed some growth/climate/natural resource/population redlines all at once?

“The only answer can be denial,” argues Paul Gilding, the veteran Australian environmentalist-entrepreneur, who described this moment in a new book called “The Great Disruption: Why the Climate Crisis Will Bring On the End of Shopping and the Birth of a New World.” “When you are surrounded by something so big that requires you to change everything about the way you think and see the world, then denial is the natural response. But the longer we wait, the bigger the response required.”

Gilding cites the work of the Global Footprint Network, an alliance of scientists, which calculates how many “planet Earths” we need to sustain our current growth rates. G.F.N. measures how much land and water area we need to produce the resources we consume and absorb our waste, using prevailing technology. On the whole, says G.F.N., we are currently growing at a rate that is using up the Earth’s resources far faster than they can be sustainably replenished, so we are eating into the future. Right now, global growth is using about 1.5 Earths. “Having only one planet makes this a rather significant problem,” says Gilding.

Read the whole thing HERE.

For those who would like to explore this topic further, I would suggest looking into the debates surrounding Neo-Malthusianism and Cornucopianism.