Penguins don't have teeth

The same as their avian relatives, penguins lack teeth. However, they do have spines inside of their beaks that might resemble a few teeth. These fleshy spines develop in rows and curve inward toward a penguin's neck. They slant inward to make it easier for the bird's prey to pass through its throat. In reality, a penguin deliberately consumes a fish head first so that its fins don't get caught as it descends. The serrated or barbed spines catch any fish or other prey that wriggles or tries to escape. Think of a fish hook with a barb on it that is intended to grab a fish so it won't escape. With the help of these barbed spines, a penguin may keep the prey it has worked so hard to catch.

These spines are also present on their tongues, and both sets of them point backward. These aid in swallowing and let them keep fish or other prey in their jaws. Penguins swallow stones but do not chew their meal. One of the interesting facts about penguins, which, despite how bizarre it may seem, is true. There is a purpose behind why penguins ingest stones of different sizes. For the fish or other prey to be digested in the bird's stomach, the pebbles aid in disassembling the various components of the prey. When assisting a penguin's digestive process, the pebbles rotate continuously. The stones acquire a smooth surface from all of this movement. With this action, little pebbles ultimately disappear. Larger stones, on the other hand, could pass completely through a penguin's digestive tract and exit the body when its feces.