'Mass Extinction: Life at the Brink' warns humans could cause next mass extinction

A new documentary 'Mass Extinction: Life at the Brink', which aired on The Smithsonian Channel, humans will be responsible for causing the next mass extinction of species.

Sean B. Carroll, evolutionary biologist and the documentary's executive producer said, "There are enough warning signs all around us. The changes we have created on the planet are similar to the ones that happened in the past when mass extinctions happened."

"Since, say, 1800, with the Industrial Revolution and the way we have fished the oceans, timbered the forests, developed the land and basically removed creatures simply through conflict or hunting or harvesting - that's the path we're on," said evolutionary biologist and documentary host Sean Carroll, according to Salon.

The Washington Post considers the African lion species an important example of dramatic population decline in the documentary, reporting that since 1950, the species has dropped in number from 500,000 to 32,000 lions left.

"We know that from historic records of where lions used to be, and where they clearly are not any more," said Anthony Barnosky, biologist at the University of California, Berkeley, who is featured in the documentary. "So it's a combination of using the historical data about what we know distributions were over the past couple of centuries, combined with some very detailed studies, censuses of how many lions are out there in known populations over the past half century."'

"What is doable, what is actionable is to strengthen, if not expand the reserves we already have," Carroll said. "Let's not wait for 160 countries to agree on something; let's act where people are both willing and able to do something. That's reserve by reserve, place by place across the world."

Mass Extinction: Life at the Brink will air at 8 p.m. ET on Sunday, Nov. 30 on the Smithsonian Channel. Watch the documentary preview shown: