Cuttlefish

Anatomy and adaptations

The internal porous shell known as the cuttlebone provides buoyancy control while a muscular mantle powers jet propulsion. Cuttlefish have large, highly mobile eyes with distinctive pupils and a brain organized for sophisticated behavior. Their limbs include eight arms and two extendable tentacles tipped with suckers used to seize prey. A hard beak and a radula help them consume food.

Camouflage, sensing and intelligence

Cuttlefish are renowned for instantaneously changing skin color, pattern and even texture. Specialized skin cells — chromatophores, iridophores and leucophores — alter appearance for camouflage, communication and hunting. Research suggests they may lack conventional color vision yet perceive polarized light and contrast, enabling nuanced display and target detection. Their problem-solving abilities and learning capacity make them subjects of cognitive studies.

Diet, predators and behaviour

They are active predators that feed on a variety of marine animals. Typical prey includes small molluscs and crustaceans such as molluscs, crabs and shrimp, along with fish and occasionally other cuttlefish. Their own predators include larger fish and marine mammals; for example, some sharks and sea predators will take cuttlefish. Hunting tactics combine stealthy color-matching, sudden tentacle strikes and precise beak bites.

Reproduction typically involves elaborate male displays, direct transfer of sperm to the female, and females laying clusters of eggs on substrates. Many species have a short life cycle, commonly living one to two years and often dying after breeding.

Humans use cuttlebone as a calcium-rich supplement for cage birds and in crafts; their ink and behavior have cultural and scientific significance. Some species are fished for food or kept in public aquaria, and research into their camouflage and neural systems informs materials science and neuroscience. Conservation issues vary by region and species, with habitat change and fishing pressure affecting local populations.