Monday 3 December 2012

With Numerous Factors being Responsible for Megafaunal decline, why was Africa least affected?


Of all the continents, Africa was the least affected by the Late Pleistocene extinction (Elias &Schreve 2007). Whilst Africa contains 42 genera of megafauna; only 7 died out during the last 100kyr. This blog will explore reasons why African megafauna remained largely untouched by forces that drove extinctions in other continents.

The genera that became extinct in Africa during the last 100 kyr include a genus of Pleistocene elephant (Elephas), a genus of African buffalo (Parmularius) and a genus of modern cattle (Bos). Consequently African megafauna only suffered a loss of about 14% of their genera in the last 100kys (Elias & Schreve 2007).

A number of hypotheses have been proposed to explain why Africa suffered such few losses. Firstly, humans evolved and coincided with megafauna in Africa. Homo sapiens lived and evolved in Africa before they spread to other continents around 200,000 BP. Many believe that this co-evolution was a major factor which ensured the survival of megafauna during this period. It is also believed that megafauna were able to adapt their behaviour to withstand human hunting practices. Similarly, Africa had favourable climatic conditions which could support a high diversity of species. This ensured that species numbers grew to a level which allowed them not become extinct. As well as this, the glacial-interglacial transition was less severe than other continents. This provided greater climatic stability for the species living in Africa, especially those that were unable to adapt to changing environmental conditions,and could easily find refuge spots. Finally, early Homo sapiens in Africa had primitive hunting technology compared to hunter gatherers of North America. This is because the Clovis hunters of North America developed more advanced technology such as stone points, which might explain why extinction was rapid in this continent. This is reinforced by Barnowsky (2004) who stated that sophisticated technology is a key driver of over kill. 

Clovis Hunting Tools
Overall, I believe the combination of these factors explains why African megafauna was least affected by the late Pleistocene extinction, and consequently suffered few losses compared to other continents. 

2 comments:

  1. Hi Josh,

    You mentioned that the people in Africa were less sophisticated hunters than Clovis hunters in North America. Do you think that they might have evolved to become better hunters?

    There is evidence of increased hunting sophistication in Africa's homo sapiens during the late Pleistocene. For example, studies of archaeological sites of earlier humans have found that eland (a type of ungulate) remains occur more frequently. Within the archaeological sites of humans who lived in the late Pleistocene/Holocene period (but under similar environmental conditions), remains of wild pigs, which were more dangerous to hunt and therefore required more sophisticated hunting techniques such as traps for example, were more prevalent than those of eland.

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  2. Hey Li,

    Interesting point! Yes and No. I believe that African hunters had the ability to evolve and become better hunters, but there was no need to. Unlike other continents, predators (hunters) and prey (megafauna) understood one another. Co-evolution enabled the survival of megafuna alongside humans. As mentioned above, Africa contained an abundance of megafauna largely due to favorable climatic conditions. This ensured the survival of megafauna, allowing them to maintain high population abundances. In a continent which has an abundance of megafauna, there would be no need to kill more, and so there was no need to evolve to become better hunters. The stability of the climate also ensured less sever glaciations/inter-glacials, this also reinforces evidence to suggest that there was no need to improve hunting styles. In comparison, the rapidly changing climatic conditions of North America might explain why Clovis hunters evolved, and consequently had more sophisticated hunting tools. Whilst this may be the case, I think that through time, improved hunting methods in Africa were inevitable. There would have always been a need to improve efficiency in hunting, which might account for the occurrence of wild pig remains.

    Hope this helps

    Josh

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