From the BBC:
Humans hunted Australia’s giant vertebrates to extinction about 40,000 years ago, the latest research published in Science has concluded.
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Human-lit fire – deliberately targeted and more frequent than lightning – had a devastating effect of plants that had previously been protected.“Any climate change at those times was modest and highly unlikely to affect the outcome,” author Matt McGlone wrote in Science.
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He said the latest study “supports a mounting number of studies that have argued that climate change was not primarily responsible for the Late Pleistocene extinctions in other parts of the continent.”