Or so says Guy McPherson, professor emeritus in the Departments of Natural Resources, and Ecology & Evolutionary Biology at the University of Arizona. Actually, he said, We're Done.
For those not inclined to wander over to read his blog, he maintains that due to global climate change, humanity will be extinct. Soon. He predicts, " ... the near-term demise of Homo sapiens," adding that "I’d give us until 2020 at the latest." Personally, I cannot think of any professional biologist that I have had at least one beer with who thought we could sustain our current civilization for long. I am classically ambivalent. Is there an eminent breakthrough in nano-technology that will make energy "free," or chemosynthesis trivial? Will we soon design genes wholesale?
I doubt it. But, I'd like to be wrong.
While I agree the methane has hit the fan, I must point out that Prof. McPherson is wrong. And I am not being an optimist.
We are well and truly screwed. But, we have been here before. There have been several radical climate events in our human evolution as dire as the one we face. From genetic data, we know that humanity experienced at least one "recent" severe population bottleneck event about 70,000 years ago. Modern humans carry a small number of genes that were "salvaged"* from two Hominid populations, the Neanderthals, and the Denisovans which are now long extinct.
J. R. Stewart, B. Stringer
"Human Evolution Out of Africa: The Role of Refugia and Climate Change" Science 16 March 2012: Vol. 335 no. 6074 pp. 1317-1321
http://www.sciencemag.org/content/335/6074/1317.short
W. Amos, J. I. Hoffman
"Evidence that two main bottleneck events shaped modern human genetic diversity" Proc. R. Soc. B 7 January 2010 vol. 277 no. 1678 131-137
http://rspb.royalsocietypublishing.org/content/277/1678/131.full
There is the possibility that few species not currently domesticated will have a "favored" position on Earth. There will soon be hundreds of millions of humans in forced migration. They will encounter people already in place, and unwilling to share. There is an ethnographic study of how people behave under highly stressed conditions; Colin M. Turnbull's "The Mountain People." This is the advantage that an anthropologist, and archaeologist has over a biologist. We recognize that humans are very nasty, and tenacious.
PS: Someone missed my point. Hundreds of millions of people will be slamming into hundreds of millions of other people. They will slaughter each other. The chaos of war favors the spread of chaos, and disease. Additional hundreds of millions of more people will be killing each other just in reaction, plus hundreds of millions more will die from famine and disease. Humanity, in a genetic sense, will be just fine with a mere few hundred thousand survivors.
*Salvaged might mean kidnapped and raped.
"No evidence of Neandertal admixture in the mitochondrial genomes of early European modern humans and contemporary Europeans" AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 146:242–252 (2011)
http://www2.webmatic.it/workO/s/113/pr-1539-file_it-Ghirotto%20AJPA.pdf
Post Script: One of Guy McPherson's blog fans wanted to know why I did not mention being a chemist in my blog profile. I was a paperboy, a janitor, and forklift driver too. I felt like focusing on my academic jobs for my blog profile.
Two good methane chemistry articles are;
R. J. Ciceron, R. S. Oreroland
1988 “BIOGEOCHEMICAL ASPECTS OF ATMOSPHERIC METHANE”
GLOBAL BIOGEOCHEMICAL CYCLES,VOL. 2, NO. 4, PAGES 299-327,
doi:10.1029/GB002i004p00299
http://www.agu.org/journals/gb/v002/i004/GB002i004p00299/GB002i004p00299.pdf
Donald J. Wuebbles, Katharine Hayhoe
2002 “Atmospheric methane and global change”
Earth-Science Reviews 57 177–210
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.173.3496&rep=rep1&type=pdf
1 comment:
As Catton suggests, we may well be headed for another bottleneck, but how wide (or narrow, depending on one's point of view) that neck will be is perhaps a matter of conjecture.
It is my personal suspicion that the Basque of Spain/France may have more to do with the Neanderthals than most of the rest of us. Their language does not fit into any of the recognized language groups. And while most human populations have an incidence of the O-negative blood group around 10% or less, amongst the Basques it is 66%. A comparison of the Basque and Neanderthal genomes might be interesting.
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