28 March 2011

The Clan of the Hippo Hunters

A trip to the Denver Zoo this weekend brought to my attention an underused tool for making sense of pre-history, along with population genetics, linguistic family relationships, archaeological evidence, the population genetics of domesticated plants and animals, cultural similarities, and ancient climate evidence. This is ancient wild plant and animal ranges.

Hippos and Rhinos

My attention was particularly focused on the historical range of the hippo and the rhino. In about 1942, both had a range that can be roughly summed up as the Sahel, East Africa, and Southern Africa to the south of the Congo Basin jungle and (at least for the hippo) the Nile River Basin. In the fifty years since then, the range of the rhino has contracted dramatically to scattered islands of wild populations, although the range of the hippo has contracted much less. Pygmy hippos are also found in the Congo basin. All of the non-pygmy hunter-gatherer societies of early Africa would have co-existed with the ancient rhinoceros.

I also found particularly interesting the ancient range of the hippo, which extended beyond Africa to essentially that part of Europe which was part of the Cardium Pottery Neolithic (about 14,000+ years after the mainland hippo went extinct) as well as additional swaths of Greece, Anatolia, Southern Persia, and the Western Coast of India right down to its Southern tip, although apparently, not into Eastern India. European hippos mostly went extinct before the last glacial maximum ca. 20,000 years ago, quite possibly as a result of modern human over hunting. But, dwarf hippos were found in Crete, Cyprus, Malta and Sicily until later dates, with the Cyprus Dwarf Hippopotamus surviving until the end of the Pleistocene or early Holocene (about ten thousand years after mainland European hippos went extinct).

It is customary to visualize early hunter-gatherer populations is mammoth hunters. But, at first, in addition to ancient members of the elephant family, there were also ancient relatives of hippos and rhinos for early hunter-gatherers to hunt. The woolly rhinoceros, for example, survived through about 8,000 B.C.E. in Western Siberia and had a range that reached as far east as Southern England in the Paleolithic. An Elasmotherium, which was an ancient rhinoceros that was the largest land animal to ever live, was dragged into a pair of caves in Southern Siberia approximately 50,000 years ago by some predator, human or otherwise.

It is easy to fall into the trap of thinking of the ancient world as similar to that of the current one and draw conclusions about human pre-history accordingly, but one has to remember that in the Out of Africa era that much of the territory that modern humans would have encountered was teaming with a wide variety of giant wild animals not adapted to human hunting techniques that would have been abundant sources of meat (although the giant predators who could have been a threat to early modern humans were more abundant as well).

For them, megafauna may have been a bit like oil is today, a resource that when used unsustainable would have eased human transition into a new technological era and wider range until exhausted.

Tapirs

The ancient range of the Tapir was also interesting. This pig-like relative of the hippo has New World varieties, found in Latin America, and is also found in Malaysia, probably because it arose prior to split of the Americas from the Old World due to continental drift. Its ancient range includes not only Southeast Asia (including all of the Sunda area that extends into Indonesia) and continues into India in a territory roughly conterminous with the region where Munda languages are spoken. The span is notable because it crosses the boundary between India and Burma has been a major barrier to East to West gene flow, roughly marking the divided between West Eurasian population genetics and East Eurasian population genetics, just as the Munda languages are an example of the Austroasiatic languages crossing this boundary.

The implication is that this apparent stark population genetic divide, rather than being a product of a natural geographic barriers (like the divide between Melanesia and Southeast Asia, the divide between Southern Europe and North Africa, the divide between North Africa and Subsaharan Africa, or the divide between South Asia and Siberia) may be of fairly recent origins, perhaps dating to the marginalization of Munda language populations during the expansion of Dravidian language speaking populations in the last few thousand years. Prior to that time, India might have had a more East Eurasian biased population genetic mix.

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