OCTO-CAMO: Octopus Camouflage

The art of camouflage: a selection of incredible and spectacular Octopus videos

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The Octopus is an extraordinary animal which has many fascinating features. One of them is its amazing transformation ability. The Octopus can morph to almost any shape and change the texture and the color of its skin extremely rapidly.  By doing that, he can hide from enemies or, on the contrary, impress them with flashing dissuasive colors. The following videos are probably the most famous: they almost look like they are fake!

Most cephalopods (which are basically mollusks with tentacles) have this ability to change color, called homochromy. The male cuttlefish displays dynamic glowing color patterns to know if another cuttlefish is a male or not.

How does it work? Well a bit like a TV flat screen. The cephalopod’s skin is made of two layers of different specialized cells which can change the apparent color, opacity, and reflectiveness of the skin. The upper layer is made of pigment bearing cells called chromatophores which are responsible for the yellow, orange, red, brown, or black color. They are like little pockets filled with ink which can be emptied when the cell is contracted. The lower layer is composed of cells containing crystals which can modify the light reflected by the skin, creating shiny, glowing or metallic effects. These cells are like pixels on a screen. The combination of the different pixels generates almost any color. Cuttlefish can even communicate between them using the light polarization. How the cephalopods manage to control and adapt the color to their environment is yet not completely understood.
Roger Hanlon from the Marine Biological Laboratory (Massachusetts) has studied these animals for a long time. His page is full of extraordinary videos. In this one, you can see how the chromatophores work:

These animals are also able to change their body shape and texture by activating tiny muscles in their skin: the papillae. That way, they can grow spikes and bumps to look exactly like seaweed or rocks.

The mimic octopus (Thaumoctopus mimicus), a specie discovered in Indonesia in the 90’s, has developed the most impressive imitation skills. It can mimicry the appearance and the behavior of a large range of animals: sea snakes, flatfish etc. Sometimes, one can’t even tell what it’s trying to seem like!

To learn more:

-Enter "cuttlefish", "mimic octopus" ou "octopus camouflage" in your search engine!

-Visit Roger Hanlon's website

-Watch this last video:

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The Ice Finger of Death

Last year, BBC cameramen  H. Miller and D. Anderson filmed the formation of an underwater icicle:

Credits: cameramen Hugh Miller and Doug Anderson for the BBC One series Frozen Planet Because it is formed by freezing brine sinking into sea water, this phenomenon has been named "brinicle".It was first described in the sixties but, because it is very difficult to know when and where it will occur, it's the first time someone has actually managed to film it.  The cameramen also have to work under extreme conditions: freezing water under a thick layer of ice. "I do remember it being a struggle... All the kit is very heavy because it has to sit on the sea bed and not move for long periods of time" says Mr. Miller How does the brinicle form? When cold water freezes, it excretes impurities (such as salt) in the crystallization process. This leads to the formation of little pockets filled with very dense salty water which does not freeze at 0°C (the salt lowers the freezing point). The brine then travels through a tiny network of channels until it reaches the sea surface. Being denser and colder than sea water, it sinks and, as it freezes the relatively warm sea water it comes in contact with, forms a thin and fragile tunnel of ice which grows into a brinicle. Brinicles don't last very long; it has to be relatively calm for them to grow. Eventually, sea currents will destroy them, often before they reach the ground. Learn more on the BBC website

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Theo Jansen's Creatures

If you have a collection of 50 000 straws, 2 liters of glue and no special plans for this summer, try building something like this:

Theo Jansen, a Dutch sculptor and engineer makes what some call "kinetic art". He builds these rather peculiar creatures who wander around, powered by the wind, on picturesque beaches. Imitating the natural selection process, he improves his models from one generation to the next.

Click on the image to visit his website:

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Up there

Talented graphic artists, an old electro-magnet found on Ebay, plastic colour balls and a lot of work: that's what it took the Physalia Studio team to create this esthetical dynamic experience. The video shows how they first had to incorporate a tiny electro-magnet into each plastic ball. A microchip enables to control individually the intensity of their electromagnetic field. After the huge bargained electromagnet is turned on, the balls levitate harmoniously.

(Click on the picture to play the video or watch it directly on the Physalia Studio website. ):

Actually, this video may be a fake; it would still be a pretty sweet graphic performance.

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Earth at night, as seen from the ISS

What can the members of the International Space Station staff possibly do when they are not conducting cool zero-gravity experiments or cleaning up the mess? They look through the window and take spectacular pictures. These time lapse videos show the dense urban areas and the desert parts of the planet, as well as atmospheric phenomena, such as lightening and aurorae.

Numerous other amzing pictures are available on the NASA's website.

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Blue Currents

This is a computer animation of ocean surface currents based on satellite observations.

Apart from being pretty, it shows how heat is transported across the planet  (influencing the local climats) and where CO2 is likely to be diluted and stocked. It also helps to track polluted waters.

The current lines remind me of the way Van Gogh sometimes painted clouds:

Nuit étoilée, Vincent Van Gogh, juin 1889

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The Lyre Bird Sound System

The Lyre Bird lives in Australia and has acquired an incredible talent in order to impress chicks: it can imitate almost anything. He impersonates at least 20 different birds perfectly as well as other animals such koalas or dingos. He has also incoporated astonishing  human caused sounds in his repertoire: camera shutters, car alarms and even chainsaws!

Make sure your speakers are on when you watch this:

  

The Lyre Bird learns from its environment and from other Lyre Birds.Tunes and sounds are passed from one generation to another. In this video, he mimicries construction work noises:

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