Huge body size may have led to extinction of mammoths

Huge body size of some giant animals such as mammoths may have been one of the contributing factors to their extinction, a new study suggests.
Researchers from Universidad de la Republica in Uruguay analysed the major food webs during the Pleistocene - a period from about 2 million years ago to 10,000 years ago - in the Americas and its possible impact on megafauna.
Several types of large animals roamed the plains of the Americas during the Pleistocene, but most of them went extinct for still unknown reasons.
Some researchers have concluded that humans wiped them out, others have suggested that it might have been due to disease or because of a comet or asteroid striking.

Others yet have suggested it might have been due to climate change.
In the new study, researchers focused on two main features: Trophic - relating to food and/or nutritional needs - and how vulnerable animals were to predation, 'Phys.Org' reported.

In mapping a wide variety of animals of all sizes on a chart using data from the two features, the team found a bell shape forming, where the large sized animals existed on the hump, suggesting they were much more vulnerable to changes in their food supply.
The researchers noted that modern animals, like elephants require 75kg to 150kg of food every day, and they live in a warm environment.

Mammoths would likely have required more food to keep warm, as would others such as the large sabre-toothed cats.
Moreover, the largest animals likely did not have to worry too much about being attacked by predators, thus, it appears likely that their large size and appetite led to their downfall, researchers said.
As climate conditions led to lesser range for such animals, they found it more and more difficult to fulfil their nutritional requirements - those that could not adapt, went extinct, they said.