Posted on 06/18/2016 2:53:34 PM PDT by SunkenCiv
"Patagonia turns out to be the Rosetta Stone - it shows that human colonisation didn't immediately result in extinctions, but only as long as it stayed cold," says study leader Professor Alan Cooper, ACAD Director. "Instead, more than 1000 years of human occupation passed before a rapid warming event occurred, and then the megafauna were extinct within a hundred years."
The researchers, including from the University of Colorado Boulder, University of New South Wales and University of Magallanes in Patagonia, studied ancient DNA extracted from radiocarbon-dated bones and teeth found in caves across Patagonia, and Tierra del Fuego, to trace the genetic history of the populations. Species such as the South American horse, giant jaguar and sabre-toothed cat, and the enormous one-tonne short-faced bear (the largest land-based mammalian carnivore) were found widely across Patagonia, but seemed to disappear shortly after humans arrived.
The pattern of rapid human colonisation through the Americas, coinciding with contrasting temperature trends in each continent, allowed the researchers to disentangle the relative impact of human arrival and climate change...
The only large species to survive were the ancestors of today's llama and alpaca - the guanaco and vicuna -- and even these species almost went extinct...
"In 1936 Fell's cave, a small rock shelter in Patagonia, was the first site in the world to show that humans had hunted Ice Age megafauna. So it seems appropriate that we're now using the bones from the area to reveal the key role of climate warming, and humans, in the megafaunal extinctions," says Dr Fabiana Martin, at the University of Magallanes.
(Excerpt) Read more at eurekalert.org ...
Because of your replies in “Farming Invented Twice In Middle East, Genomes Study Reveals”, thought you might like to see this one.
So megafauna extinction happened during the same time in Patagonia as in the Middle East? Pretty amazing that human techniques for effectively killing them off developed at the exact same time on opposite sides of the earth. I don’t believe that coincidence such as this is a random happenstance.
extinction corresponds with cosmic dust peaks or beryllium-10 spikes
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