Paleontologists have been debating for decades about the causes that led to the extinction of megafauna at the end of the Pleistocene, between 40,000 and 12,000 years ago . This category usually includes large terrestrial animals that have already disappeared, such as the mammoth, the deer of the genus Megaloceros , the woolly rhinos or the mastodons. However, it would also bring together some species that still survive today, such as elephants.
Some experts maintain that these enormous animals were exterminated by our ancestors ; others, that disappeared as a result of some cataclysm or perhaps due to climate change. Now, a team of scientists from the University of the Republic, in Uruguay, delves into this last possibility and suggests that one of the factors that could contribute to all this was the great size of these creatures.
In a study published in the journal Biology Letters , ecologists Angel Segura and Matías Arim and paleontologist Richard Fariña analyze how the availability of food during the last ice age would have influenced megafauna, especially in America, where they have focused their research. These experts have compared the nutritional needs of these animals and the resources present before and after they became extinct and have assessed the extent to which the different species were vulnerable to predators. In this way, they were able to determine that the largest ones were, in turn, those that were the worst adapted to changes in diet.
In the case of mammoths, for example, carnivores may have posed a lesser threat. But an alteration in the climate would have significantly reduced its food source – an elephant consumes more than 200 kilos of food a day; the mammoths would probably need more – precipitating their decline. Over time it would be increasingly difficult to find enough to survive.
Image: Flying Puffin via Wikimedia / CC
