This is the scene of a turtle feeding on jellyfish, which is one of the main food sources for turtles.
Many people think jellyfish are harmless, but they're actually cnidarians, a group of animals equipped with specialized cells called cnidocytes that can easily puncture the skin and inject toxins.
While all jellyfish can sting, sea turtles seem unfazed by them. Being reptiles with tough outer skin that can resist cnidocytes makes sense, but what about inside their mouths?
Well, sea turtle mouths are quite formidable too.
Here's a peek inside a sea turtle's mouth, filled with hardened spines that extend all the way down to the stomach, looking rather intimidating:
The spines in a sea turtle's mouth allow them to eat jellyfish, but that's not their primary function. These spines are believed to have evolved to trap food. When sea turtles ingest food, they also swallow seawater, which needs to be expelled. The function of the spines in the mouth is to retain food while filtering out seawater. Different marine animals have various physiological structures for filtering seawater and retaining food, but sea turtles might be among the most unfortunate. This feature of a sea turtle's mouth makes them major victims of marine debris. Once they ingest items like plastic bags, the spines securely trap them, making it impossible for the turtles to free themselves. Moreover, plastic bags float in the ocean and are easily mistaken for jellyfish by sea turtles.
