A team of scientists say humans have changed the planet so dramatically, that we have created a new geological era on Earth — called the Anthropocene. That team spent years trying to find where a place on Earth best exemplifies this phenomenon. They decided on a lake in Southern Ontario in Canada. The World’s host Marco Werman discusses this decision with Francine McCarthy, a professor of Earth science at Brock University in Canada, who is part of the international Anthropocene Working Group.