The tooth about giant extinctions

Did humans wipe out native megafauna? In North America and Australia this has been a contentions issue amongst palaeontologists and indigenous people. One camp say people did the job while the others say it was climatic and environmental factors.

See fellow Fuzzy Caitlin's Cosmos story about new dating for giant kangaroo Protemnodon, showing that it was around when the first people arrived 40,000 to 43,000 years ago.

"..carbon dating the bones as well as pollen samples lodged deep inside the long nose of the Protemnodon skulls.." were used for the dating (I wonder if they suffered hayfever?).

This discovery places both humans and Protemnodon in Tasmania at the same time, so the evidence is circumstantial. In fact I don't imagine that anything like definitive proof is ever possible, trying to establish cause and effect 40,000 years ago. However I have heard of models for North American large mammals, showing that a kill rate of only a couple of percent would be enough to exterminate a species.

Looking forward to more Caitlin Cosmos stories.

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