What do bison, beaver, wolves and sea otters all have in common?They're keystone species. That means they have an outsized impact on their ecosystem. It took humans driving some of these to near extinction to realize just how important they are.Now animals like the American Bison and North American Beaver are some of the Endangered Species Act's most notable success stories. As part of our series marking the 50th anniversary of the Endangered Species Act, we're taking a closer look at the efforts to save keystone species.Want to support 1A? Give to your local public radio station and subscribe to this podcast. Have questions? Find out how to connect with us by visiting our website.Learn more about sponsor message choices: podcastchoices.com/adchoicesNPR Privacy Policy