Biologists say half of all species could be extinct by end of century

Scientists at Vatican conference are searching for a solution to the manmade 'major extinction event'

One in five species on Earth now faces extinction, and that will rise to 50% by the end of the century unless urgent action is taken. That is the stark view of the world's leading biologists, ecologists and economists who will gather on Monday to determine the social and economic changes needed to save the planet's biosphere.

"The living fabric of the world is slipping through our fingers without our showing much sign of caring," say the organisers of the Biological Extinction conference held at the Vatican this week.