The even Lonelier Planet: Half the world's species are facing extinction by end of century

Destruction of wildlife areas for farming and logging is the biggest cause of falling animal numbers, claim experts meeting at Biological Extinction conference

Half the world’s animal species could face extinction by the end of the century unless urgent action is taken, scientists warn.

One in five are currently under threat, but it could rocket as the human population soars from 7.4billion now to 11.2 billion by 2100 as estimated by the UN.

Destruction of wildlife areas for farming and logging is the biggest cause of falling animal numbers, claim experts meeting today at the Biological Extinction conference.

US biologist Paul Ehrlich, of Stanford University in California, believes greater use of birth control is key to reducing our impact on the environment. He said: “If you value people, you want to have the maximum number you can support sustainably.

“You do not want almost 12 billion living unsustainably on Earth by the end of the century – with the result that civilisation will collapse and there are only a few hundred survivors.”

He added: “We are wrecking our planet’s life support systems. We have the capacity to stop that.”

Around 11,000 conservative Catholics have signed a petition calling on Pope Francis to withdraw Prof Ehrlich from today’s conference at the Vatican.

It is one of a series there on ecological issues, which the Pope deems an urgent issue for the Catholic church.

The experts say that while animals such as the tiger or rhino make headlines, too little attention is paid to the eradication of most other life forms.

Just 15% of the world’s land is currently protected for nature.

Prof Peter Raven, of the Missouri Botanical Garden, said: “By the beginning of the next century we face the prospect of losing half our wildlife.

“The extinctions pose a greater threat to civilisation than climate change – for the simple reason they are irreversible.”