Have you ever noticed that warning about raw or undercooked seafood at the bottom of restaurant menus? Ever wondered why it's there? Because fish carry a ton of parasites, and if they aren't prepared correctly then those parasites can make it into your body. But it turns out, this intersection can teach us a lot about how these moochers help keep ecosystems healthy, and why we should protect them.

Originally released by Knowledgemotion, 2018. Streaming video file encoded with permission for digital streaming by Infobase on February 21, 2020.

Will You Still Eat Raw Fish After Watching This Video? (6:32); .