Human population explosion started well before the neolithic

It has generally been accepted that by the time the last glacial ended around 12-13,000 years ago the world-wide human population was between 4 – 6  milllion people and as agriculture and a settled life style began population exploded reaching about 60-70 million by about 6,ooo years ago (4,000BCE).

Last year Chinese researchers suggested from genetic studies that the population probably began expanding some time before the neolithic probably after the Last Glacial Maximum (around 25,000 years ago) but before the establishment of the full inter-glacial conditions in the Holocene neolithic. This appears logical since even during the glacial period the conditions around the equator and tropics would have been relatively mild and fertile.

The authors suggest that the milder climate after the Last Glacial Maximum may have offered a more amiable environment and may have been an important factor in prehistoric human expansions. The increase in population size was probably one of the driving forces that led to the introduction of agriculture, turning it from a supplementary food source to the primary one.

But a new paper now suggests that population expansions probably began much earlier and even before herding and agriculture were established already while humans were predominantly hunter-gatherers. This would have been in the paleolithic and perhaps 60,000 – 80,000 years ago.

Human genetic data reveal contrasting demographic patterns between sedentary and nomadic populations that predate the emergence of farming, C. Aiméa, G. Laval, E. Patin, P. Verdu, L. Ségurel, R. Chaix, T. Hegay,   l. Quintana-Murci, E. Heyer and F. Austerlitz, Mol Biol Evol (2013) doi: 10.1093/molbev/mst156

Science Daily:

Now, researchers Aiméa, et al., have challenged this assumption using a large set of populations from diverse geographical regions (20 different genomic regions and mitochondrial DNA of individuals from 66 African and Eurasian populations), and compared their genetic results with archaeological findings. The dispersal and expansion of Neolithic culture from the Middle East has recently been associated with the distribution of human genetic markers.

They conclude that the first significant expansion of human populations appears to be much older than the emergence of farming and herding, dating back to the Paleolithic (60,000-80,000 years ago) rather than Neolithic age. Therefore, hunter-gatherer populations were able to thrive with cultural and social advances that allowed for the expansion. The authors also speculate that this Paleolithic human population expansion may be linked to the emergence of newer, more advanced hunting technologies or a rapid environmental change to dryer climates.

Finally, they also suggest that strong Paleolithic expansions may have favored the emergence of sedentary farming in some populations during the Neolithic. Indeed, the authors also demonstrate that the populations who adopted a sedentary farming lifestyle during the Neolithic had previously experienced the strongest Paleolithic expansions. Conversely, contemporary nomadic herder populations in Eurasia experienced moderate Paleolithic expansions, and no expansions were detected for nomadic hunter-gatherers in Africa. “Human populations could have started to increase in Paleolithic times, and strong Paleolithic expansions in some populations may have ultimately favored their shift toward agriculture during the Neolithic,” said Aiméa.

A semi-nomadic herding life-style with temporary settlements could well have allowed sufficient resources for population expansions and also have been consistent with the geographical expansions of humans.

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About ktwop

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2 Responses to Human population explosion started well before the neolithic

  1. Pingback: Ancient humans coped with massive climate change (without the IPCC) | The k2p blog

  2. Richard W. Posner says:

    Archaeological evidence from locations such as Gobekli Tepe , in southeastern Turkey, indicates that, at least eleven thousand years ago, Neolithic humans started building large structures, temples, places for ritualistic gatherings. At the same time, most significantly and most damning, they began to think of themselves as separate from and superior to all other Life of Earth.

    “Anthropologists have assumed that organized religion began as a way of salving the tensions that inevitably arose when hunter-gatherers settled down, became farmers, and developed large societies. Gobekli Tepe, to Schmidt’s way of thinking, suggests a reversal of that scenario: The construction of a massive temple by a group of foragers is evidence that organized religion could have come before the rise of agriculture and other aspects of civilization. It suggests that the human impulse to gather for sacred rituals arose as humans shifted from seeing themselves as part of the natural world to seeking mastery over it” (emphasis added). (source)

    http://wp.me/p5dUI4-RX

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