Octopuses possess unique feeding structures. While they do not have teeth like vertebrates, these intelligent marine creatures are equipped with specialized tools for processing their prey.
The Octopus’s Beak
Located at the center of their eight arms, where the mouth is positioned, octopuses have a hard, parrot-like beak. This beak is the only rigid part of an octopus’s otherwise soft body, allowing it to squeeze through any opening its beak can fit through. It is composed primarily of chitin, a durable yet lightweight material also found in the exoskeletons of insects and crustaceans. This composition makes the beak resistant to corrosion and decay.
The beak consists of two parts: an upper and a lower mandible that work together in a scissor-like fashion. The upper beak typically sits within the lower beak, giving octopuses an underbite when closed. This strong structure functions to bite and crush the hard shells of prey such as crabs, clams, and other shellfish. Its robust nature enables the octopus to break down food before it is ingested, serving as a primary tool for processing tough prey.
The Radula
Octopuses possess another distinct feeding apparatus called the radula. This ribbon-like organ is covered with multiple rows of chitinous denticles, often described as tiny, rasping teeth. While these are sometimes referred to as “teeth,” they are not analogous to the bony teeth found in mammals; instead, they function more like a conveyor belt or a chainsaw. The radula is supported by cartilages and muscles, allowing it to move forward and scrape food.
Each row on the radula typically contains seven to nine individual denticles. As the octopus feeds, the front denticles wear down, and new ones continuously form from behind, ensuring the radula remains effective. The radula’s primary function is to scrape or grind food into smaller pieces, preparing it for digestion.
How Octopuses Feed
Octopuses are active predators, consuming a diet primarily consisting of crustaceans, mollusks, and sometimes fish. Their feeding strategy involves a coordinated effort between their arms, beak, and radula, often coupled with venom. An octopus typically envelops its prey with its arms, using the powerful suction cups to secure it.
For hard-shelled prey, the octopus uses its beak to bite through or chip away at the shell. Some species also employ a specialized salivary papilla, which can drill a precise hole into the shell. Through this hole or a break in the shell, the octopus injects venom, a mixture of toxins and enzymes produced in its salivary glands. This venom paralyzes the prey and begins to liquefy its internal tissues.
Once the prey is subdued and its tissues are softened, the radula comes into play, scraping the meat and drawing it into the esophagus. The beak also assists in cutting softer foods into manageable, bite-sized portions. This integrated process allows octopuses to efficiently access the nutritious soft parts of their prey, even those protected by tough outer coverings.