Leading biologists estimate nearly half of the planet’s species could be extinct by the end of the century unless urgent action is taken.

A major conference to be held at the Vatican is bringing together prominent biologists, ecologists and economists as part of the Biological Extinction conference in a bid to halt the mass extinction.

The three-day event, jointly sponsored by the pontifical academy of science and pontifical academy of social sciences, aims to find a solution to save the planet’s diversity.

A pamphlet on the workshop, due to start on 27 February, says: “The living fabric of the world is slipping through our fingers without our showing much sign of caring.”

Citing statistics from the Intergovernmental Panel on Climate Change (IPCC), the earth is on course to see 20 to 40 per cent of all biodiversity wiped out by the end of the 21st century.

And while there is a concerted effort to protect endangered species such as pandas, tigers and rhinos, other organisms are being overlooked.

The Biological Extinction statement said: “All of our food comes directly or indirectly from higher plants, of which there are an estimated 425,000 species.

"Tens of thousands of these have been cultivated for food at some time by some people, but at present, 103 of them produce about 90 per cent of our food worldwide, while three kinds of grain, maize, rice, and wheat, produce about 60 per cent of the total.

“We have detailed knowledge of perhaps only a fifth of the species of plants in the world, and a majority could be gone in nature by the end of the century we entered recently.

"The same can be said for other groups of organisms, on which we depend for many of our medicines, ecosystem services, atmospheric purification, carbon storage, and everything that really makes our lives possible.”

Critically endangered species Show all 10 1 /10 Critically endangered species Critically endangered species Yangtze Finless Porpoise There are as few as 1,000 of this highly intelligent dolphin from the Chinese river of Yangtze. Wikmedia Critically endangered species Cross River Gorilla There are around 200-300 left in the wild. Wikmedia Critically endangered species The Amur Leopard There are only around 30 left, exclusively in the Russian Far East. Wikmedia Critically endangered species Black Rhino Improving numbers, but with fewer than 5,000 left in central Africa, it is critically endangered. Wikmedia Critically endangered species Hawskbill Sea Turtle Mostly threatened by wildlife trade; their shells highly valued. Wikmedia Critically endangered species Javan Rhino The most threatened rhino species - there are as few as 35 in Ujung Kulon National Park in Java, Indonesia. Wikmedia Critically endangered species Leatherback Turtle Having lost many of its habitable beaches, and impacted by fishing operations, this seaturtle is considered by WWF to be 'critically endangered'. Wikmedia Critically endangered species South China Tiger It is believed to be 'functionally extinct', with none of the species left in the wild. Wikmedia Critically endangered species Sumatran Elephant There are between 2,400 - 2,800 of this elephant native to Borneo and Sumatra. Wikmedia Critically endangered species Sumatran Orangutan There are an est. 7,300 but the gradual deforestation of their Sumatran habitat may threaten further. Wikmedia

Pope Francis has declared the potential environmental crisis an urgent issue for the Catholic church, and the event is one of a series organised by the Vatican.

Some 26 participants are scheduled to take part in the event, including professor of population studies at Stamford University, Paul Erlich, whose views on population control have proved controversial.

He claims birth control should be more widely used to help keep numbers down, and in response to his involvement in the event a petition has been set up calling on the pope to withdraw his permission to speak.

He told The Guardian: “I believe they have about 11,000 signatures. The pope has not changed his mind, however.

“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.”