As humans continue to destroy the habitat of larger creatures, the average animal size is set to "shrink" by 25 per cent over the next century, according to a new study.
Larger, less adaptable, slow-lived species like tawny eagles and rhinos will become extinct, while smaller and adaptable creatures like rodents, dwarf gerbils and songbirds are likely to predominate, researchers at the University of Southampton said.
Unless radical action is taken to protect wildlife and restore habitats, whole ecosystems could collapse.
“By far the biggest threat to birds and mammals is humankind – with habitats being destroyed due to our impact on the planet, such as deforestation, hunting, intensive farming, urbanisation and the effects of global warming," said Rob Cooke, lead author of the study published in the journal Nature Communications.
“The substantial ‘downsizing’ of species which we forecast could incur further negative impacts for the long-term sustainability of ecology and evolution. This downsizing may be happening due to the effects of ecological change but, ironically, with the loss of species which perform unique functions within our global ecosystem, it could also end up as a driver of change, too.”
The predicted declines are particularly large when compared to the 14 per cent body size reduction observed in species since the last interglacial period 130,000 years ago.
“We have demonstrated that the projected loss of mammals and birds will not be ecologically random – rather a selective process where certain creatures will be filtered out, depending on their traits and vulnerability to ecological change," said Felix Eigenbrod, a professor at the University of Southampton.
