Still no consensus on cause of Late Quaternary mass extinction

Studies reach opposite conclusions on humans vs climate change debate

The cause of the mass extinction of megafauna (land-living species with an adult mass of over 45 kg (100 lb)) during the last Ice Age has been debated since the late eighteenth century. Two main theories have predominated for much of that time: human causation and climate change. Two new studies, published in the journals Science and Ecography respectively, suggest that the debate is set to continue. Continue reading

Deep Impact?

Why an asteroid impact is unlikely to have caused the Late Quaternary mass extinction.

The Pleistocene world was dominated by large mammals, flightless birds and reptiles. These included mammoths, mastodons, giant ground sloths, camels, sabre-tooth cats, giant beavers, and giant deer with antlers spanning 3 m (10 ft.). In Australia, there lived the hippopotamus-sized Diprotodon optatum that weighed in at 2.8 tonnes, and was the largest marsupial of all time. These animals are collectively known as the megafauna, a term applied to animals with an adult weight of 45 kg (100 lb.) or more. Between 50,000 and 10,000 years ago, many of these great beasts vanished in one of the largest extinction events since the demise of the dinosaurs.
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