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Related: About this forumNo evidence for theory humans wiped out megafauna
No evidence for theory humans wiped out megafauna
The research challenges the claim that humans were primarily responsible for the demise of the megafauna in a proposed "extinction window" between 40,000 and 50,000 years ago, and points the finger instead at climate change.
An international team led by the University of New South Wales, and including researchers at the University of Queensland, the University of New England, and the University of Washington, carried out the study. It is published in the Proceedings of the National Academy of Sciences.
"The interpretation that humans drove the extinction rests on assumptions that increasingly have been shown to be incorrect. Humans may have played some role in the loss of those species that were still surviving when people arrived about 45,000 to 50,000 years ago but this also needs to be demonstrated," said Associate Professor Stephen Wroe, from UNSW, the lead author of the study.
"There has never been any direct evidence of humans preying on extinct megafauna in Sahul, or even of a tool-kit that was appropriate for big-game hunting," he said.
Read more at: http://phys.org/news/2013-05-evidence-theory-humans-megafauna.html#jCp
Warpy
(110,913 posts)The human population adapted, abandoning the beautifully crafted large spear heads and arrow tips of the Clovis people for a larger quantity of less well crafted arrowheads for smaller game.
They still aren't quite sure what caused the Younger Dryas, only that it was sudden and incredibly dramatic.
Ichingcarpenter
(36,988 posts)not North American megafauna which is on a slightly different time frame , the weapons the aborigines used never could have taken down the big beasts of their land, 8 to 14 megafauna species still existing when Aboriginal people arrived.
The
megafauna loss is still a mystery to me which I think maybe cosmic in origin such as a super flare from our sun or nova explosion which somehow effected the planet's ecosystem over thousands of years.Mankind was just a small part of the equation on the demise of superfauna. Interesting stuff because I think we know more about the dinosaurs than man's short history on the planet
Warpy
(110,913 posts)because our ancestors thoughtlessly left us so few things beyond their fire pits, stone tools, and the bones of the animals they ate. Their languages, jokes, tall tales, and strategies to get through the day are long gone.
The Australian Aborigines are the oldest continuing culture on the planet, their songlines detailing not only a map of the continent, but also their oldest tall tales, some of which might contain keys to the demise of the megafauna. My advice to paleontologists in Oz is to pay a little less attention to bones and more to translating those songlines. Their ancestors were certainly there to see it happen. The oldest aboriginal art might also give a clue or three.
During any climate change, the non adaptable large fauna are the first to go. One wonders if this is another Great Extinction when the planet sorts itself out differently and new life forms arise to take advantage of new conditions.
AverageJoe90
(10,745 posts)Regardless of how bad climate change gets.....Barring, perhaps, a Yellowstone eruption AND a K/T event, or some other combination of truly cosmically catastrophic events, in the near future.....
Though I can agree with one thing: Talk to the indigenous people of the old New World cultures. Try to decode the old tales and see what we can find.
Warpy
(110,913 posts)from a "fire mountain," probably the last volcano that erupted about an hour west of me something like 15,000 years ago.
Tribal peoples have been fairly stable in this region, the land is so poor and the water so lacking that nobody else wanted to fight them for it.
AverageJoe90
(10,745 posts)Warpy
(110,913 posts)AverageJoe90
(10,745 posts)Family went thru Albuquerque during the summer of '10 on their way to Ariz.
NickB79
(19,114 posts)And it's been used successfully for hundreds of thousands of years.
http://news.nationalgeographic.com/news/2005/07/0707_050707_aussieextinct.html
The exact purpose of the fires is unclear; the settlers may have been clearing land, signaling other tribes, or hunting. What is clear is that the fires changed the landscape from a mosaic of forests and grasses to the fire-adapted shrubs and spinifix (a grass) found today.
Climate change is often thought to have caused extinctions in other parts of the world. The researchers were able to eliminate this possibility by studying the carbon isotopes of the eggshells of emus and the teeth of wombats going back 140,000 years. There were many large climate shifts during that period that did not induce a change in the ecosystem. In addition, evidence from dust in marine sediments off the coast of Australia suggests that the climate was relatively stable 45,000 to 50,000 years ago.
However, the evidence showed a clear shift in the diet of many animals 45,000 years ago.
sofa king
(10,857 posts)I once saw an old film of Kalihari Bushmen hunting a giraffe. They worked together to distract the giraffe so that one guy got in a position to wound it (with a spear in that case, I barely recall), then they tracked it for three days and caught up to it when it died. I don't remember much after that, but I think the rest of the tribe relocated to the kill.
A fire-wall could be used to bring your megafauna prey to you first, or to corner it, and then to prevent it from running too far away while you play the Komodo dragon waiting game.
The San tribe of the Kalihari still hunts big game with poisoned arrows, probably not unlike people did 50,000 years ago:
The ramifications of a tribe wounding and/or poisoning big game and then relocating to the position where the animal died may be quite important. The 'ologists may be spending a lot of their time looking for logical placement of settlements, when those settlements may have actually been semi-randomly positioned according to where some giant critter finally keeled over.