After stalking a cuttlefish, a moray eel finally pounces. As the eel snags the mollusk in its teeth, its prey struggles to escape. But before it can wiggle away, a second set of teeth lunge from the eel’s throat. This adaptation is called a pharyngeal jaw, and is one of the most common adaptations under the sea. Darien Satterfield shares how this incredible skeletal mechanism works. Lesson by Darien Satterfield, directed by Zack Williams.