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Frozen in Time: What Caused the Extinction of the Ice Age Megafauna?

© Yukon Government, Art by George "Rinaldino" Teichmann

The megafauna of Siberia and Alaska included muskoxen, bison, wild horses and woolly mammoths. © Yukon Government, Art by George "Rinaldino" Teichmann

By Simon Ho

A new study of ancient DNA preserved in permafrost has revealed that Ice Age megafauna varied considerably in their ability to survive climate change and the spread of humans.

Simon Ho is a Senior Lecturer and an Australian Research Council Queen Elizabeth II Research Fellow in the School of Biological Sciences at the University of Sydney.

The full text of this article can be purchased from Informit.

Over the past 50,000 years the world has lost many of its large animals. Among the “megafauna” species that disappeared were iconic mammals like the woolly mammoth and woolly rhinoceros, which roamed the tundra during the last Ice Age. The intensity and timing of these megafauna extinctions varied among different regions of the world.

The reasons for these extinctions have long been a source of interest to researchers and the general public alike. Scientists in the early 19th century, including Georges Cuvier, William Buckland and Louis Agassiz, believed that the megafauna were wiped out by catastrophic geological events such as floods.

But after it was demonstrated that humans actually co-existed with some of the species of megafauna, there was a growing suspicion that overhunting played a role in the extinctions. Such noted biologists as Richard Owen and Alfred Russel Wallace placed the blame on humans.

Now the debate has seen most researchers falling into one of two camps, with the argument revolving around the impacts of climate change and humans. Did the megafauna succumb to the effects of a changing climate? Or did humans drive them to extinction by hunting them, modifying their habitat, or introducing diseases?

It is also important to consider why other large animals, such as those that we see today in the African fauna, managed to...

The full text of this article can be purchased from Informit.