BEACON TRANSCRIPT – The matter has been long debated, but new research found that human hunters may have caused the extinction of woolly mammoths, with a bigger role played than climate change. The two theories have been long discussed.
Some scientists believed that climate change had the most vicious impact on the ice age large animals, while others contest humans as their biggest threat. The issue has also seen attempts at a slight middle ground. Several experts claim that a combination between the two have led the huge mammals to extinction.
However, a new study conducted by researchers at the University of Michigan aims to tip the balance in the favor of humans. Or against them, depending on the perspective, considering hunters are being blamed. The two researchers, doctoral student Michael Cherney, and his advisor, Dan Fisher, have examined a collection of tusks.
Woolly mammoths are believed to have lived between 10,000 and 40,000 years ago, in certain regions across North America and Siberia. Their tusks are an important part that could provide with incredible information about their diet and health. They created an additional layer in each year of the mammal’s life, thus contains valuable information.
The two researchers examined a number of 15 different tusks, investigating their chemical structure to determine changes throughout the years. By using an isotopic signature, they found that weaning age (the moment when a calf stops nursing from their mother) decreased by 3 years within the 30,000 years that led to their extinction.
This indicates pressures applied to mature much more quickly due to excessive hunting. Advanced maturation is often a consequence found in animals when faced with stress due to hunters. Early weaning is a clear sign of quicker maturation. Which means that humans had a much bigger impact leading to the moment of their extinction than believed.
In fact, climate change tends to create the exact opposite effects of what the researchers found. Due to nutritional stress, it’s commonly results in delayed weaning. According to Cherney, their findings are, thus, inconsistent with the notion that climate change might’ve led to the extinction of woolly mammoths.
Their research have certainly not led to the definitive conclusion, and it’s likely that the debate will continue for many years to come. However, the same patterns are visible in elephants, for example. During the stress induced by climate change, today’s elephants delay the weaning process because of the drought.
The early weaning which was hinted by the tusks fits better with the theory that human hunters were the cause of their extinction.
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