Eels are aquatic animals known for their elongated bodies and fluid movements. Their distinctive, snake-like appearance often leads to questions about their internal structure and how they navigate diverse aquatic environments. These creatures are found across various habitats, from shallow coastal waters to deep ocean trenches.
Eels Are Vertebrates
Eels are fish, classified within the order Anguilliformes, and like all fish, they are vertebrates. This means they possess an internal skeletal system, including a backbone. Their skeletal framework comprises a skull and a vertebral column that runs the length of their body. The eel’s skull is typically elongated and narrow, conforming to its serpentine body plan.
The vertebral column, or spine, provides the main support for their long, flexible bodies. This spine is composed of numerous small vertebrae, which link together to form a highly mobile chain. Eels often have a greater number of these bony segments, enabling their characteristic movement and allowing them to maintain body shape while swimming.
Skeletal Adaptations for Movement
Eels employ a swimming technique known as anguilliform locomotion, where their entire body undulates in wave-like motions from head to tail. This movement is possible due to their supple vertebral column, which contains a high number of vertebrae. Most eels have between 100 and 200 vertebrae, though some species, like snipe eels, can possess as many as 500.
This specialized skeletal design allows eels to navigate through tight spaces, burrow into substrates, and move efficiently through complex underwater environments. The muscles surrounding the vertebral column work in concert with the bony structure to produce these sinuous movements. During significant life stages, such as long migrations, eels can resorb cellular bone from their skeletons to free up minerals for energy metabolism. Despite this process, the structural integrity of their vertebral column is maintained, ensuring they can continue to swim effectively.
Culinary Considerations
From a culinary standpoint, eels do have bones, and they are typically numerous and fine throughout their flesh. This can make them challenging to eat, leading to a common perception that they are “boneless” when prepared. In many culinary preparations, the main spine is removed during filleting.
However, smaller pin bones often remain embedded in the meat. These can be managed through various cooking methods; for example, broiling can soften them to the point where they are barely noticeable or even edible.
Beyond the meat, eel bones are sometimes utilized in dishes, such as being fried into crunchy bone crackers or used to make flavorful broths, offering nutritional benefits like calcium.