How Moving Light Can Change a Cuttlefish’s Skin Texture

A cuttlefish can change the physical relief of its skin. Small muscular projections called papillae can rise or flatten, altering the animal’s three-dimensional appearance. This ability adds a remarkable layer to the colour changes for which cephalopods are famous. Understanding it requires asking both how the skin moves and what the animal sees. [2] [3]

A peer-reviewed study in the 15 August 2025 issue of the Journal of Experimental Biology examined the visual trigger. Christian Drerup and colleagues tested common cuttlefish, Sepia officinalis, under controlled laboratory lighting. [1]

The finding at a glance

• Cuttlefish skin texture is actively controlled by muscles.
• Moving light bands could elicit raised papillae even without a rock stimulus.
• A stronger skin response did not establish improved concealment from predators.

The bumps are living, movable structures

Papillae are part of a muscular system within the skin. A 2018 physiology study investigated the nerves and muscles controlling their expression and relaxation. The researchers identified motor control associated with the stellate ganglion, a peripheral nerve centre, and described a combination of smooth and striated muscles. This is active shape control by soft tissue, allowing the surface to change without growing a new covering. [2]

The work also found sustained tension without ongoing neural stimulation in experimental preparations. The research institution’s original account describes papillae remaining extended for more than an hour. This is a useful distinction between initiating a movement and maintaining a configuration: the control requirements can differ. The authors described a catch-like mechanism that could reduce the need for continuous activation, rather than demonstrating that maintaining the skin costs no energy. [2] [7]

Vision can guide the response without touching a rough surface

A 2009 study compared natural substrates with two alternatives: the same substrates covered by glass, and laminated photographs of them. Glass removed direct tactile information; photographs also removed the actual three-dimensional surface. Key papillae responses persisted across these presentations, supporting visual guidance of the skin’s texture. The researchers also reported variation among papilla types, leaving details of their control open. [3]

The important idea is that the animal can respond to the appearance of a surface. A textured object produces patterns of bright and dark areas, edges and spatial variation. Those features can be visible in a flat photograph as well as on the object itself. Consequently, an apparent match between an animal’s skin and a nearby rock does not by itself identify which visual information produced the response.

Changing texture can accompany a change in disguise

In a 2017 study, researchers examined cuttlefish responses to different rocks. A smooth white rock was associated with a uniform body pattern and relatively smooth skin. A rock carrying contrasting shell fragments elicited mottling and stronger papillae expression. Responses were reversible as the objects changed. The work linked an animal’s choice of position, body pattern and skin texture within the same behavioural sequence. [4]

This relates to masquerade, in which an animal resembles an object rather than being recognized as prey. The concept concerns an observer’s classification of what it sees. Documenting the cuttlefish’s response is one part of the problem; determining how a predator interprets that appearance is another. Keeping those questions separate makes subsequent camouflage experiments more informative. [4]

Moving water changes the image reaching the eye

Underwater light is not always steady. A moving water surface can bend and concentrate illumination into shifting bright bands, known as caustics. These can change the contrast within a scene even when the objects remain still. The animal therefore receives a changing image without a corresponding change in the physical texture of the seafloor. [5]

A 2024 study investigated this problem for cuttlefish body patterns. Under moving light bands, the animals displayed stronger disruptive patterns on both plain and patterned backgrounds. Disruptive patterning can break up the apparent body outline. That study concerned pattern expression; the 2025 research extended the question to raised skin structures. Together, the experiments investigate different parts of a visually guided response. [5]

What the 2025 researchers measured

The study used 20 cuttlefish. Four rock types combined smooth or textured surfaces with grey or multicoloured appearances; an empty cylinder provided a no-rock condition. Rocks were enclosed behind glass. Each condition was tested under steady grey illumination and moving light bands. [1]

Researchers scored six papilla groups from 0 to 3, producing a total between 0 and 18. Infrared images concealed the projected lighting patterns from the scoring process. Moving light elicited papillae without a rock, while maximum scene contrast was associated with expression strength. Additional light bands did not further increase expression beside every already-coloured or textured rock. [1]

A measured reaction still needs a functional explanation

One interpretation is that raised skin helps disrupt the animal’s outline in a visually complicated environment. Another is that the visual system responds to contrast without fully separating cues from object surfaces and cues from illumination. These alternatives were discussed by the researchers. They concern why a response occurs and whether it is useful, not a dispute about the observed skin response. [1] [5]

The papilla score was not a measure of how invisible an animal became. The experiments did not test predator detection, and a controlled projection cannot represent every combination of depth, water movement and background found in nature. Establishing a camouflage benefit would require evidence from an observer’s visual task. The distinction is especially important when a striking animal response is described as an adaptation.

Why changeable texture interests engineers

The engineering connection predates the featured experiment. In 2017, James Pikul and colleagues reported stretchable synthetic surfaces inspired by cephalopod muscular morphology. Their system combined elastic membranes with relatively inextensible textile mesh. Inflation transformed initially flat surfaces into designed three-dimensional textures resembling features such as stones and plants. The shapes emerged from the organization of the material, not from copying living cuttlefish skin. [6]

That work demonstrates an engineering route for controlling surface shape. The animal studies add a complementary question: how should a responsive surface select a shape from visual input? A possible research direction would combine sensing, a defined visual objective and a controllable material, then test performance under changing illumination. This is an implication for future work, not a new device established by the 2025 cuttlefish study.

A useful next experiment would ask whether the same skin response changes detection by an appropriate observer under different lighting conditions. The cuttlefish’s ability is already remarkable. Explaining when it is triggered, and when it improves concealment, reveals how muscles, visual information and a changing environment work together.

Sources and references

1. Drerup C, How MJ, Herbert-Read JE. Visual contrast from background features and dynamic illumination contributes to three-dimensional camouflage in cuttlefish. Journal of Experimental Biology 228(16), jeb249713 (2025). Issue dated 15 August 2025. Peer-reviewed research.
2. Gonzalez-Bellido PT, Scaros AT, Hanlon RT, Wardill TJ. Neural Control of Dynamic 3-Dimensional Skin Papillae for Cuttlefish Camouflage. iScience 1, 24–34 (2018).
3. Allen JJ, Mäthger LM, Barbosa A, Hanlon RT. Cuttlefish use visual cues to control three-dimensional skin papillae for camouflage. Journal of Comparative Physiology A 195, 547–555 (2009).
4. Panetta D, Buresch K, Hanlon RT. Dynamic masquerade with morphing three-dimensional skin in cuttlefish. Biology Letters 13(3), 20170070 (2017).
5. Drerup C, Dunkley K, How MJ, Herbert-Read JE. Cuttlefish adopt disruptive camouflage under dynamic lighting. Current Biology 34(14), 3258–3264.e5 (2024).
6. Pikul JH, Li S, Bai H, Hanlon RT, Cohen I, Shepherd RF. Stretchable surfaces with programmable 3D texture morphing for synthetic camouflaging skins. Science 358(6360), 210–214 (2017).
7. Kenney D, Marine Biological Laboratory. How the Cuttlefish Spikes Out its Skin: Neurological Study Reveals Surprising Control. Original research-institution account, 15 February 2018.