Moisture might have played a big part in the extinction of megafauna at the end of the Ice Age

At the decline of the last Ice Age, some 11 – 15 000 years ago, the megafauna rapidly went extinct as the climate grew hotter, and researchers at the University of Adelaide recently published a paper describing how moisture played a key role in their extinction. The exact reason why this mass extinction took place is currently unknown, but this paper goes a long way to prove that the climate change was responsible.

The megafauna from the last Ice Age is known as the Pleistocene megafauna, and in this context it means any animal larger than 44kg in body mass. The word megafauna is latin, and can simply be translated into something like “big animal”. These megafuna include well-known animals such as mammoths (Mammuthus spp.), woolly rhinoceros (Coelodonta antiquitatis), mega deer species (Megaloceros spp.) and Eurasian cave lions(Panthera leo spelaea).

This is what the woolly rhinoceros looked like, one of the many megafauna species that went extinct at the end of the previous Ice Age. This is obviously a reconstruction, and not a real individual. Image by Wikimedia user Sémhur, posted with the Free Art License.

The study is based on herbivores, but it is possible that the extinction of the large predators naturally followed once the large herbivores died out. The theory they have suggested is that following the melting of permafrost and glaciers, the moisture in the air would increase. This data was backed by collection of nitrogen isotopes, found in animal bones from this time period.

The theory further includes that the increased moisture levels would change the entire environment, and the grassland which was needed by the large herbivores were mostly transformed into peatlands and bogs. This would in turn fragment the herbivore population, and combined with other environmental changes linked to the increased temperature, lead to their extinction.

What is really exciting is that data from both America, Siberia and Europe, so we can see a clear trend that took place on a global scale. This means that the extinction event was likely taking place at the entire earth at the same time, which means that it probably was something to do with the climate, and not things like disease or other population-depended factors.

No one knows the exact reason why the megafauna went extinct, but this new theory gives us a lot of new knowledge about this event. There are surely more factors that lead to the extinction of so many animals, and I’m sure more papers will be published in the future, which will shed more light on the extinction during the end of the previous Ice Age.

Learning about the previous Ice Age might seem pointless to many people, but we are currently living in the worst mass extinction event the world has ever seen, and I’m sure knowledge about previous mass extinctions will be vital information to help us stop the ongoing process we are currently facing.

Thanks for reading, and make sure to follow me for more ecology and biology posts!

Sources

The paper was published in Nature Ecology and Evolution, and you can find it by clicking here. You can read the abstract for free, but unless you have connections to a university, it is going to cost you a lot to get full access.