Top 10 Amazing Facts About Cuttlefish

With green blood, three hearts, and able to change colour in a flash, it sounds like a ‘weird aliens’ movie creature ~ Paula Weston
The amazing cuttlefish belongs to the class "cephalopoda", the same family which octopus and squid belong to.

Spectacular lavender cuttlefish
Spectacular lavender cuttlefish

Cuttlefish at Georgia Aquarium

Not only does the cuttlefish have the characteristics described above but it is also considered to have the highest intelligence of any invertebrate, as well as the ability to see backwards, use jet propulsion and keep buoyancy in the same way that submarines do. Oh, it shoots jets of ink as well!

 10. Cuttlefish bone is filled with gas!
Pfeffers Flamboyant Cuttlefish

Cuttle-bone (the things you see in bird cages) has small chambers and like a submarine, filling or releasing the gas in them controls the cuttlefish's buoyancy.

9. The flesh of the Flamboyant Cuttlefish is poisonous
Close-up of cuttlefish head

This is the only species of cuttlefish known to have any poisons and it carries a unique toxin in its muscles. This species is also short and stubby, unlike the long graceful bodies of most others.

8. The cuttlefish eye is shaped like a W.

Sepia latimanus (reef cuttlefish) with dark coloration, seconds before turning white

The unique shape of the pupils plays a part in the most highly developed eyes of any animal. They allow the cuttlefish to perceive light polarization and completely reshape their eyes to focus. They also really do have the proverbial eyes in the back of the head, with a second spot on the fovea which allows them to see backwards.

7. Cuttlefish can change color in mere seconds

Sepia latimanus (reef cuttlefish) with white coloration. Seconds prior, this individual was dark in coloration.

The beautiful pink reef cuttlefish seen here and in the previous image is actually the same fish. The two pictures were taken just seconds apart, cuttlefish change color using a series of special skin cells, chromatophores, iridophores and leucophores, which reflect light in all sorts of colors.

6. Cuttle fish can make themselves completely invisible

Infant Cuttlefish Shows Camouflage

Not only do they reflect colors, they are able to merge almost completely with the seafloor.

5.Cuttlefish shoot jets of ink
Common cuttlefish Sepia esculenta

Cuttlefish ink was the original sepia which was once used by artists - nowadays replaced mostly with synthetic sepia. The ink is used as a defense to confuse predators and allow the cuttlefish time to escape.

4. Cuttlefish don't have a tail
They have a fin all the way around their body instead of tail fins, like squid, and they use this fin to control movement.

3. Cuttlefish have jet propulsion
Pharaoh Cuttlefish using its rocket propulsion, Moyo Island

Cuttlefish can escape from enemies by using rocket propulsion. Water is squeezed down their body (mantle) into a special tubular muscle (siphon) that controls the direction as they are propelled backwards for a short distance

2. Cuttlefish have green blood

Large cuttlefish Sepia apama from Komodo National Park

Their blood is green because it uses the protein hemocyanin which has copper in it rather than hemoglobin.

1. Cuttlefish have 3 hearts
Cuttlefish, Great Barrier Reef, Cairns, Australia

The blood is pumped by three separate hearts: two branchial hearts pump blood to the cuttlefish's pair of gills (one heart for each), and the third pumps blood around the rest of the body. Cuttlefish blood must flow more rapidly than that of most other animals because hemocyanin carries substantially less oxygen than hemoglobin.

These amazing animals (cephalopods) are so unique and beautiful. Even submarines have made use of their buoyancy methods and they have physical characteristics that no other animal has, yet most of us only know them by the piece of cuttle-bone in a bird cage. Hopefully these facts have led you to admire them as much as I do.