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View Full Version : Lembeh Straights Flambouyant Cuttlefish



Sarah
02-04-2007, 06:55 AM
Nice little guy!

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allisonfinch
04-05-2007, 09:37 PM
:)
I really loved my interactions with them. They were totally unfazed by divers. As it turns out, their "cuttle bones" are so reduced, compared to other cuttlefish, they can only swim for short distances. That is why they are always walking. Also, imagine my surprise to find out that they are extremely toxic!! No wonder their posturing says "I'm dangerous...don't touch!!"

As soon as I can figure out how to post some pictures on the board (Chick, give me directions!) I will post some.

Sarah
04-05-2007, 10:38 PM
Hi Allison,

There are 2 main ways to make photos appear here. One is to just add them when the new post or post reply window comes up, the lower of which will say: "Additional options" Under that, there is "Attach files" and click on manage attachments. Then a window will open up that will search hierarchically on your computer.....then just click on the file you want. it can't be too large.

The other way is to serve it up somewhere, then post the link using BB code.

The last way is to e-mail me the image, I will serve it up, or post it in the Gallery here, (you can post it in the SM Gallery also) make your text post, I will insert it into your post for you.

Let me know whatever help you need. :)

As to cuttlefish, we're working on an HD video production and here is the copyrighted narration text that will be finalized for the cuttlefish portion:

"The cuttlefish belongs to the mollusk class Cephalopoda—which means ‘head-footed’ derived from the Greek words kephale (head) and podes (feet)—ranging from around one inch in length to the giant Australian cuttlefish, which can reach lengths of 5 feet.

Most molluscs possess an external shell consisting of one or two parts, such as oysters, abalone, scallops and snails. The shell in most cephalopods has been reduced in size (or completely lost) and shifted to the inside of the body to form a structure more like a backbone, and it is this cuttlebone which you may have seen that when dried, is*sometimes given to parakeets and other caged birds as a source of calcium, essential salts and minerals.


The cuttlefish fills tiny compartments in its cuttlebone with gas to help maintain neutral buoyancy. However, if the depth changes, so will the amount of bouyancy from the water. Therefore in order to be able to operate at varying depths and water densities, cuttlefish need to be able to adjust their overall density so as to always remain neutrally bouyant. The cuttlefish does this by an ingenious mechanism. The bony shell actually has many narrow hollow chambers. If these were all filled with gas, they would give a positive lift of up to 4% of the animal’s weight. The cuttlefish is able to pump liquid in and out of that section as needed to keep neutrally bouyant.

The bone is within the body part of the animal called the mantle and attached to the mantle is a head with eight arms and two feeding tentacles that normally are retracted to just under the aniamls cheeks.

The cuttlefish is an ambush predator and a master of disguise. Its skin is covered with special cells called chromatophores, iridophores and leucophores that reflect light in many different colours enabling the cuttlefish to blend into its background almost perfectly. Some say it's like a chameleon but it is far superior in its ability to change colour, texture and shape of it’s body and the orientation of it’s arms to mimic plants.

Cuttlefish will use its camouflage to steadily sneak up on its prey. Their preferred diet is crabs or fish, and when it is close enough it opens apart its eight arms and out shoots two deceptively long feeding tentacles. On the end of each is a pad covered in suckers that grasp hold of the prey and quickly pull it close to the cuttlefish's mouth that looks like a parrot's beak.

The scientific name for a cuttlefish is Sepia. In years gone by sepia ink, which is derived from cuttlefish, was used by artists for their paintings. For the cuttlefish this ink is a decoy, a means of escape from predators. If a large fish were to attack a cuttlefish it could eject a cloud of almost black ink towards its attacker. The predator would get a mouthful of ink that is a signficiant irritant to the attackers mucous membranes and gills. Meanwhile the cuttlefish is hidden from view and propels itself away backwards by using its own jet propulsion system, its siphon. Their siphon is highly controllable by the cuttlefish who can gimble the nozzle for direction control as well as increase or reduce the nozzle exit diameter to control jet velocity. This is similar to modern day American jet fighters like the F-22 Raptor who have vectorable jet engine nozzles for extreme maneuverability and speed control.

In addition of its direction siphon nozzle, for stabilizers cuttlefish have bilateral symmetrical finlike apendages that they undulate for forward, rearward or turning locomotion.

Unlike mammals which use a red, iron containing protein called hemoglobin in their blood, Cuttlefish blood looks blue-green because it uses the copper containing pigment hemocyanin to carry oxygen, unlike our blood which uses the red pigment hemoglobin. Hemocyanins are respiratory and metalloproteins containing two copper atoms that reversibly bind a single oxygen molecule (O2). Oxygenation causes a color change between the colorless Cu(I) deoxygenated form and the blue Cu(II) oxygenated form. Hemocyanins carry oxygen in the blood of most molluscs, and some arthropods such as the horseshoe crab. The blood in the cuttlefish is pumped by three separate hearts, two of which are used for pumping blood to the cuttlefish's pair of gills (one heart for each gill), and the third for pumping blood around the rest of the body. A cuttlefish's heart must pump a higher blood flow than most other animals because hemocyanin is substantially less efficient for carrying oxygen than hemoglobin.

The cuttlefish has a skin comprising three layers of colour pigment cells called chromatophores—a bright yellow layer near the surface, under which is an orange-red layer and finally a dark base. Transformation from one colour to another, which can take less than a second, is controlled by the central nervous system. In just a few seconds, it can run a whole gamut of colours.


Their skin flashes a fast-changing pattern as communication to other cuttlefish and to camouflage them from predators. This color-changing function is produced by groups of red, yellow, brown, and black pigmented chromatophores above a layer of reflective iridophores and leucophores, with up to 200 of these specialized pigment cells per square millimeter. The pigmented chromatophores have a sac of pigment and a large membrane that is folded when retracted. There are 6-20 small muscle cells on the sides which can contract to squash the elastic sac into a disc against the skin. Yellow chromatophores (xanthophores) are closest to the surface of the skin, red and orange are below (erythrophores), and brown or black are just above the iridophore layer (melanophores). The iridophores reflect blue and green light. Iridophores are plates of chitin or protein, which can reflect the environment around a cuttlefish. They are responsible for the metallic blues, greens, golds, and silvers often seen on cuttlefish. All of these cells can be used in combinations. For example: orange would be produced by red and yellow chromatophores, while purple could be created by a red chromatophore and an iridophore. The cuttlefish could also use an iridophore and a yellow chromatophore to produce a brighter green. As well as being able to influence the color of the light that reflects off their skin, cuttlefish can also affect the light's polarization.

In addition to using color changing for camoflage, in some species of cuttelfish a male will aggressively stand guard over a female while she lays her eggs to keep away predators and other competing males. But another male cuttlefish can still access the female by adopting female colouration along the side of its body facing the defending male as it passes by. At the same time, it will retain its male colouration on the side facing the female.

Cuttlefish eyes are among the most developed in the animal kingdom. They have similar eyes to humans, but the pupil is a smoothly-curving "w" shape. Although they cannot see color, they can perceive the polarization of light, which essentially enhances their perception of contrast. They have two spots of concentrated sensor cells on their retina, one to look more forward, and one to look more backwards. The lenses, instead of being reshaped by muscular contraction as they are in humans, are instead moved coaxially by reshaping the entire eye in order to change focus."