Big beasts face extinction as habitats evolve

BIG mammals including the elephant, rhinoceros and hippopotamus could vanish within the next 100 years as smaller creatures, able to adapt to more confined habitats, flourish.

Researchers at Southampton University found that the body mass of mammals will collectively reduce by 25 per cent over the next century as humans further encroach on to their land.

Although most of the reduction will be caused by the extinction of large animals, some bigger creatures may actually shrink in size as they are forced to deal with smaller habitats.

Experts studied nearly 15,500 mammals and birds and used computer modelling to predict how expected habitat loss would affect populations.

While creatures like the Asian elephant, Javan rhinoceros and giraffe will struggle with habitat loss, animals expected to flourish include the brown rat, bush rat and blackbird, which are more adaptable.

Rob Cooke, lead author of the study published in the journal Nature Communications, said: “By far the biggest threat to birds and mammals is humans – with habitats being destroyed due to deforestation, hunting, intensive farming, urbanisation and the effects of global warming.

“The substantial downsizing of species that we forecast could incur further negative impacts for the long-term sustainability of ecology and evolution.

“In the future, small, fastlived, highly fertile insecteating animals that can thrive in a wide variety of habitats, will predominate.”

Many scientists believe the Earth has already entered a sixth mass extinction event with animals now dying out at 100 times the normal rate, scientists said.

Humans have created a toxic mix of habitat loss, pollution and climate change, which has already led to the loss of at least 77 species of mammals, 140 types of bird and 34 amphibians since 1500.