Humankind Evolving: Navigating "Windows" Of Opportunity Into Survival Or Extinction

The old appeals to racial, sexual and religious chauvinism and to rabid nationalism are beginning not to work. A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. - Carl Sagan

UPDATE:  Here's a great writeup on the Toba volcano eruption and its probable impact on human evolution @ 60,000BP - Toba Catastrophe Theory.

ORIGINAL POST
At the end of Wednesday evening's regular meeting of Fayette Freethinkers here in north central Georgia we ventured into the very murky matter of the future of Humankind.  A fellow member asked for more details about an assertion I made.  In the course of the discussion I boldly and somewhat naively allowed my right brain holistic hopes elbow out my left brain parsimony, as usual.

I asserted that our species has a successful track record of passing through a number of narrow evolutionary "passages" - to get through some of these we used our brains, others our tools, others our feet, and still others we were just plain lucky.  That this success rate was a good enough reason for me to be optimistic about Humankind passing through the current window of evolutionary "trial" - tribalism, nationalism, "religionism", and environmental willful ignorance and indifference, and their various consequences such as war and life-threatening pollution.

Fortunately, in my zeal, I was coherent enough to make clear that my optimistic view of Humankind's future was probabilistic, not one of certainty.  After all, evolutionarily, our species is batting a thousand in American baseball parlance.  We could, however, very easily, through our own efforts or lack of effort, or due to causes beyond our control, not make it through another window such as the one we are now facing.  It's of course every person's choice as to where s/he thinks our species will end up - be optimistic about our species' survival and work to help make it come about, or be pessimistic that we won't, do nothing about it, and await the realization of the gloom and doom we fear and the fate of extinction 99% of life on Earth has succumbed to.

At the meeting, a small, casual and professionally and politically diverse group of "freethinkers", I presented the example of the vanguard of our fully human ancestors in the Horn of Africa @ 60,000BP, numbering less than a few thousand at the time.  This group, their backs turned to the increasingly arid environment of the Horn and the rest of East and Southern Africa, nevertheless successfully migrated through what appears to be a route near the mouth of the Red Sea into South Asia and thereby avoided extinction.  Their improbable penchant for "success" ultimately allowed our species to establish populations in the rest of Asia, Australasia and Europe, and ultimately back in Africa.

Christopher Hitchens once cited this example from our incredible list of good fortunes claiming that the total population of Homo sapiens alive at 60,000BP had declined to less than 2,000 individuals (click here).  I have so far been unable to find a reference that supports this very low number.  [If any of you know one please let me know.]  It is likely an extrapolation from DNA or mitochondrial statistical analysis.  For now, here is an excellent article published by the Proceedings of the National Academy of Sciences on the subject:  Why Did Human Populations Disperse From Africa 60,000 Years Ago? A New Model by Paul Mellars.

For more on this topic see my posts, The Driving Forces of Human Evolution - A Reading List, Cultural Evolution, Phase II - Establishing A Unified Worldview, and Human Evolution: Expansion Of Humans Out Of Africa Into Asia Earlier Than Previously Known.  I will also be posting more on this topic in the coming months.

Happy 2012!