Scientists say planet in midst of sixth mass extinction, Earth’s wildlife running out of places to live

In what year will the human population grow too large for the Earth to sustain? The answer is about 1970, according to research by the World Wildlife Fund. In 1970, the planet’s 3 and a half billion people were sustainable. But on this New Year’s Day, the population is 8 billion. Today, wild plants and animals are running out of places to live. The scientists you’re about to meet say the Earth is suffering a crisis of mass extinction on a scale unseen since the dinosaurs. We’re going to show you a possible solution, but first, have a look at how humanity is already suffering from the vanishing wild.

Here, the vanishing wild scuttled a way of life that began with native tribes a 1,000 years ago.

Paul Ehrlich: Too many people, too much consumption and growth mania.

At the age of 90, biologist Paul Ehrlich may have lived long enough to see some of his dire prophecies come true. 

Scott Pelley: You seem to be saying that humanity is not sustainable?

Paul Ehrlich: Oh, humanity is not sustainable. To maintain our lifestyle (yours and mine, basically) for the entire planet, you’d need five more Earths. Not clear where they’re gonna come from.

Scott Pelley: Just in terms of the resources that would be required?

Paul Ehrlich: Resources that would be required, the systems that support our lives, which of course are the biodiversity that we’re wiping out. Humanity is very busily sitting on a limb that we’re sawing off.

In 1968, Ehrlich, a biology professor at Stanford, became a doomsday celebrity with a bestseller forecasting the collapse of nature. 

Scott Pelley: When “The Population Bomb” came out, you were described as an alarmist. 

Finding solutions to the problems was the goal, two weeks ago, at the U.N. Biodiversity Conference, where nations agreed to conservation targets. But at the same meeting in 2010, those nations agreed to limit the destruction of the Earth by 2020—and not one of those goals was met. This, despite thousands of studies including the continuing research of Stanford biologist Paul Ehrlich.

Scott Pelley: You know that there is no political will to do any of the things that you’re recommending.

Mexican ecologist Gerardo Ceballos is one of the world’s leading scientists on extinction. He told us the only solution is to save the one third of the Earth that remains wild. To prove it, he’s running a 3,000-square-mile experiment. In the Calakmul Biosphere Reserve near Guatemala, he is paying family farmers to stop cutting the forest.

Gerardo Ceballos: We’re going to pay each family certain amount of money that is more than you will get cutting down the forest, if you protect it 

Scott Pelley: And how much are you paying out every year?

Gerardo Ceballos: For instance, each family here will get around $1,000. 

More than enough, here, to make up for lost farmland. In total, the payouts come to $1.5 million a year. Or about $2,000 per square mile. The tab is paid through the charity of wealthy donors. 

Gerardo Ceballos: the investment to protect what is left is, I mean, really small 

The five mass extinctions of the ancient past were caused by natural calamities—volcanoes, and an asteroid. Today, if the science is right, humanity may have to survive a sixth mass extinction in a world of its own making.

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