Global warming could destroy a quarter of all species of plants and animals on earth by 2050 in one of the biggest mass extinctions since the dinosaurs, according to an international study.
The United Nations said the report, highlighting threats to creatures ranging from Australian butterflies to Spanish eagles, showed a need for the world to back the Kyoto protocol, meant to brake rising temperatures linked to human pollution.
"A quarter of all species of plants and land animals, or more than a million in all, could be driven to extinction," said Chris Thomas, professor of Conservation Biology at England's University of Leeds.
Thomas, lead author of the study published in the science journal
Nature, said emissions from cars and
factories could push temperatures up to levels not seen for one million to 30 million years by the end of the century, threatening many habitats.
The survey, the largest of its kind to date, studied global warming links to 1,103 species of plants, mammals, birds, reptiles, frogs and insects in South Africa, Brazil, Europe, Australia, Mexico and Costa Rica and extrapolated findings as far as 2050. It did not examine the oceans.
"Climate change is the biggest new extinction threat," said Lee Hannah, a co-author, at Conservation International in Washington DC. Many species would simply be unable to adapt or migrate to new habitats.
Thomas said the feared extinctions could be one of the worst since the dinosaurs were wiped out 65 million years ago.