A very interesting video about cephalopod skin, with great images!
It also explains an experience designed to determine how much of the color changes is controlled by the brain or by the skin itself.
From the video:
While it’s still early to say, one possibility is that the skin itself is able to see and stimulate the chromatophores locally, bypassing the brain. A recent study at the Marine Biological Laboratory in Woods Hole, Mass., indicates that cuttlefish skin has light-sensing cells.
Txch This Week: Shape-Shifting Liquid Metal Alloys And Camo Squid Skin Technology
by Jared Kershner
This week on Txchnologist, we watched the world’s first 3-D printed car hit the road after being made in a mere 44 hours. The vehicle, called Strati, was sent on a test drive last Saturday after being quickly printed and assembled by a Local Motors team days before. The company plans to offer 3-D printed vehicles for sale in the coming months, paving the way for innovation in automotive design and opening new doors for modern manufacturing.
The creators of an MIT project called Local Warming are pioneering a heating system that uses motion sensing to direct infrared energy beams at occupants of a space, heating them directly while the remaining space stays cold. With current space heating accounting for 37 percent of the total power consumed by U.S. buildings in 2010, funding programs that rethink how to keep people comfortable could spark a radical shift in greater building energy efficiency nationwide.
Smog-producing low-level ozone concentrations are rising globally and bringing with them heightened public health and ecological threats. Scientists studying the environmental dangers of ozone offer a simple solution—plant more trees. Their models have shown that the reforestation of regions directly abutting urban areas provides an effective tool for abating ground-level ozone pollution, and could complement technology-based controls.
Now we’re bringing you the news and trends we’ve been following this week in the world of science, technology and innovation.
Does light have anything to do with how the spots change size
I assume you’re talking about this gifset. For people who haven’t seen it before, this is a closeup of squid skin.
THE SHORT ANSWER: Light affects how the spots change size by triggering a brain signal.
THE LONG ANSWER: The spots are called chromatophores. They are basically (but not simply) sacs of pigment surrounded by a ring of roughly 15-25 muscles that contract or relax. When the muscles around a chromatophore contract, they pull the chromatophore out and make it look bigger. When they relax, the color spot looks smaller.
Single chromatophores do not change size independently. Sets of chromatophores are connected to each other at a nerve. When a nerve is stimulated, all the chromatophores in that group all react at the same time. There are many groups like this in a squid’s skin, each connected to a separate nerve.
The nerves are in turn stimulated by signals passed along a neural network, meaning that the chromatophores essentially change at the speed of thought. Neural signaling is important to differentiate from hormonal signaling, which is a slower biological system that can signal and start body-wide changes.
Because they’re controlled by a neural signal from the brain, the chromatophores change size when the squid is consciously or unconsciously reacting to a change in its environment, such as light.
This should mean that if the squid is brain-dead, the spots will not change size. However, human scientists can plug directly into the nerves in charge of chromatophores and stimulate them with a different kind of signal – like music. See Backyard Brains’ Insane in the Chromatophores for a demonstration of neural hacking.
If you want to know more about how cephalopods change color, I suggest reading this.
Cephalopod dynamic camouflage, by Roger Hanlon, 2007. Free!
Cephalopod Neural Networks, by Roddy Williamson and Abdesslam CHrachri, 2003. A tougher read, also for free here.
Cephalopod chromatophores: neurobiology and natural history, by JB Messenger, 2001. Paywalled here.
Octopuses and squids are cephalopods, sea creatures that can rapidly change the color of their skin to camouflage themselves or to communicate with others.
The animals accomplish this with cells known as chromatophores, which contain pouches of pigment and are adhered to the creatures’ skin. Muscles around the chromatophores make these cells expand, turning them darker, or contract to turn them ligther.
Scientists have created a system that mimicks how the skin of these sea creatures work by involving soft, elastic materials that function as “muscles” that can change in size and shape in response to electrical signals in matter of seconds.
The Artificial Squid Skin can be utilized for camoulfage suits to benefit and most probably save lives of soldiers at war. As this material is not infrared-vulnerable, soldiers would still be safe at night. Besides camoulfaging, cephalopod´s skin could be useful in rescue operations if they are made of atention-grabbing and dynamic patterns.