![The Discovery Files show](https://d3dthqtvwic6y7.cloudfront.net/podcast-covers/000/014/590/small/the-discovery-files.jpg)
Summary: A new study led by Oregan State University shows that declining populations of "apex" predators such as wolves, lions or sharks has led to a huge increase in smaller "mesopredators" that are causing major economic and ecological disruptions.