Incredible Cuttlefish Camouflage Secrets Revealed [VIDEO]
Through studying the cuttlefish, scientists hope the mollusk will reveal clues to its natural adaptive camouflage abilities, which could be reverse-engineered and applied to future technologies.
Writing in this week's edition of the Journal of the Royal Society: Interface, researchers from Harvard University and the Marine Biological Laboratory detail their analysis of the cuttlefish's sophisticated biomolecular nanophotonic system that enables the "chameleon of the sea" to dramatically change colors and shapes.
"Nature solved the riddle of adaptive camouflage a long time ago," said Harvard's Kevin Kit Parker. "Now the challenge is to reverse-engineer this system in a cost-efficient, synthetic system that is amenable to mass manufacturing."
Parker is a professor of bioengineering and applied physics at Harvard, as well as a faculty member at Wyss Institute for Biologically Inspired Engineering at Harvard. He is also an Army reservist who has completed two tours of duty in Afghanistan, where he gained first-hand experience with how necessary camouflage is for soldiers on the ground, and the life-saving potential of better camouflage technology.
"Throughout history, people have dreamed of having an 'invisible suit,'" Parker said. "Nature solved that problem, and now it's up to us to replicate this genius so, like the cuttlefish, we can avoid our predators."
Besides using bio-inspired technology to develop textiles for camouflage, the practice could have a range of other applications including in paints, cosmetics and consumer electronics.
Research into the natural adaptive camouflage seen in cuttlefish, pencil squid and other creatures has been ongoing for years. In the cuttlefish (Sepia officinalis) the color-shifting is achieved through pigmented organs called chromatophores that respond to neural signals and visual cues. Cuttlefish can do a lot more than just change color, the mollusks can change the shape and texture of their bodies to blend in with their surroundings. The surface area of cuttlefish skin can expand as much as 500 percent.
Parker and his colleagues' latest research details the biological, chemical, and optical functions that make this adaptive camouflage possible.
"The cuttlefish uses an ingenious approach to materials composition and structure, one that we have never employed in our engineered displays," said study co-author Evelyn Hu, Tarr-Coyne, also of Harvard. "It is extremely challenging for us to replicate the mechanisms that the cuttlefish uses. For example, we cannot yet engineer materials that have the elasticity to expand 500 times in surface area. And were we able to do so, the richness of color of the expanded and unexpanded material would be dramatically different-think of stretching and shrinking a balloon. The cuttlefish may have found a way to compensate for this change in richness of color by being an 'active' light emitter, not simply modulating light through passive reflection."
Roger Hanlon and his colleagues at the Marine Biological Laboratory in Woods Hole, Mass., also contributed to the study.
"Cuttlefish skin is unique for its dynamic patterning and speed of change," Hanlon said. "Deciphering the relative roles of pigments and reflectors in soft, flexible skin is a key step to translating the principles of actuation to materials science and engineering. This collaborative project expanded our breadth of inquiry and uncovered several useful surprises, such as the tether system that connects the individual pigment granules."