I am sceptical. As you say yourself, African (and Indian) megafauna are AGGRESSIVE. They do not fear human beings. The response of an elephant to being threatened by a human being is to attack and crush the annoying little hominid. Cape Buffalo and rhinos and hippos are also aggressive. (Not to mention crocodiles.) The things are effectively bullet-proof except to large-caliber weapons. What's some guy with a spear going to do? Other than die, I mean.
It is true that apex predators do not normally feed on people (except crocodiles), but I think that that is likely because human beings have not been around for long enough to become any species' customary food source. (Not to mention that by the time human beings were sufficiently numerous to be able to serve in this way they were already technologically advanced and therefore harder to get).
--- On Fri, 12/26/08, Somebody Somebody <philos_case at yahoo.com> wrote:
> Date: Friday, December 26, 2008, 5:57 AM
> Briefly, the notion is that the survival of megafauna in
> Africa is actually compelling evidence for the so-called
> "overkill" hypothesis of human hunting leading the
> Pleistocene/Holocene mass extinctions. Because humans
> evolved in Africa over several million years, the large
> animals there co-evolved with intelligent hominids and
> developed a natural wariness of man. There may have been an
> early Pleistocene extinction attributable to early hominids.
> I would also note that despite having many large species,
> including ones like buffalo and zebra evolutionarily close
> to domesticated ones, almost no African animals have ever
> been tamed and made useful for husbandry, because they tend
> to be too aggressive and wild.
>
> The evidence is very suggestive. Very shortly after the
> arrival of humans into Australia, which as this paper
> indicates, has been increasingly narrowed to around 50,000
> years ago, the enormous diprodont wombats, giant short-faced
> kangaroos, marsupial lions, and megalania a 20 foot lizard
> all become extinct. Again, the arrival of the Clovis culture
> in North America, coincides with the disappearence of
> mammoths, mastodons, native horses, giant beavers, and
> short-faced bears. These extinctions occur in regional
> pulses at different times that seem to match with local
> arrival of human populations, not like the
> Cretaceous-Paleogene extinction of the dinosaurs, which was
> global in nature.
>
> From the Proceedings of the National Academy of Sciences of
> the U.S.A.:
>
>
> Megafauna biomass tradeoff as a driver of Quaternary and
> future extinctions
> 1. Anthony D. Barnosky*
>
>
> Extinction intensity varied by continent, with Australia,
> South America, and North America hard-hit, losing 88% (14
> extinct, 2
> surviving), 83% (48 globally extinct, 2 extinct on the
> continent, 10
> surviving), and 72% (28 globally extinct, 6 extinct on the
> continent,
> 13 surviving), respectively, of their megafauna mammal
> genera. Eurasia
> lost only 35% of its genera (4 globally extinct, 5 extinct
> on the
> continent, 17 surviving). Africa was little affected, with
> only 21%
> loss (7 globally extinct, 3 extinct on the continent, 38
> surviving),
> including at least three Holocene extinctions.
>
>
> Humans evolved in
> Africa, and hominins have been interacting there with
> megafauna longer
> than anywhere else. Insofar as they are dated, there is no
> correlation
> between human arrival or climate change for the few African
> extinctions. In general, extinctions in Australia
> intensified within a
> few thousand years of human arrival ≈50 kyr B.P. but did
> not correspond
> with unusual climate change. Extinctions in northern
> Eurasia
> corresponded in time with the first arrival and population
> expansions
> of H. sapiens,
> but both pulses also were concentrated in a time of
> dramatic climate
> change, the first pulse at the cooling into the Late
> Glacial Maximum
> (LGM) and the second pulse at the rapid fluctuation of YD
> cooling
> followed by Holocene warming (2, 4). Other species of Homo
> had been interacting with the megafauna for at least 400,000
> years without significant extinctions before H. sapiens
> arrived. In Alaska and the Yukon, the first pulse of
> extinctions
> corresponded with LGM cooling but in the absence of
> significant human
> presence; the second pulse coincided with humans crossing
> the Bering
> Land Bridge and with the YD and Holocene climatic events.
> In central
> North America, extinction was sudden and fast, coinciding
> with the
> first entry of Clovis hunters, the YD–Holocene climatic
> transition, and
> the purported comet explosion. In South America, humans
> were already
> present by 14.6 kyr B.P., megafauna did not start going
> extinct until
> Holocene warming commenced some 11 kyr B.P., and species of
> ground-sloths, saber cats, glyptodonts, and horses have
> seemingly
> reliable radiocarbon dates as young as 8 kyr B.P. (21).
> Link:
> <http://www.pnas.org/content/105/suppl.1/11543.full>
>
> Online book dealing with the issue:
> <http://www.megafauna.com/>
>
>
> ___________________________________
> http://mailman.lbo-talk.org/mailman/listinfo/lbo-talk