Cephalopodes

Spread across 300 different species the Octopus is a soft limbed mollusc which has eight limbs to use. It is a bilaterally symmetrical animal and has two eyes and a beak. Thanks to its soft body the octopus can change shape and move around in between nooks and corners too. When they move around the eight appendages tend to follow them.

It is said that an Octopus has a complex nervous system but obviously good eyesight and thus are the most behaviourally diverse of all invertebrates. You will find an octopus in various parts of the sea like pelagic waters, coral reefs and the sea beds. Most of the species of octopus grow very quickly leading to early maturity and subsequent death.

Octopus has been aptly used in various forms of mythology and certain fantasy books as well. The entire world loves to eat the octopus but usually, the Mediterranean and Asian areas are true lovers of the same. Giant Pacific octopus has been found to be the largest of the entire octopus available. On the other hand, the Octopus wolfi is smallest with an average length of 2.5 centimetres. It also has an ink sac for protection which can be found under its digestive gland.

Also called the cuttles these molluscs fall under the order of Sepiida. They are known for having an internal shell which goes by the name the cuttlebone. Their distinctive feature is the presence of large W shaped pupils, two tentacles and eight arms. These tentacles have suckers using which they trap their prey and hold it tightly. Their Average size ranges from 15-20 centimetres though the longest variety seen went up to a length of 50 centimetres.

The diet of a cuttlefish includes other cuttlefish, shrimps, molluscs, crab and octopus. The average life expectancy of the cuttlefish is between one to two years and their predators are sharks, dolphins, seals, fishes etc. Similar to other molluscs these also have abundant stores of ink in their bodies. This ink is released when these fish are supposedly attacked.

The cuttlefish ink is used for multiple purposes like making the food sweet, flavour rice and pasta, and for dyeing plastics and other materials. Cuttlefish also have a camouflage facility which they use to change the colour of their skin. This trick is aptly used to hunt and scare their prey and attack them.

Cephalopods by origin Squids have large eyes, elongated bodies, two tentacles and eight arms. Similar to other counterparts they have a mantle, distinct head and bilateral symmetry. Just like an octopus, they have a very soft body but it has a small skeleton which is shaped like a pen. They use their two tentacles to grab the prey and the eight arms to hold it tight.

The beak they have is used to cut the prey into pieces and swallow it. They usually locate their prey and then by jet propulsion move very quickly to reach and attack it. Surprisingly squids are considered to be the most intelligent of all the invertebrates found on earth. Squids can also camouflage and escape from predators. They are bioluminescent and use the light also for camouflage.

In commercial fisheries found in Japan, the Mediterranean, the south-western Atlantic, the eastern Pacific the squid are nurtured for consumption. Also called Calamari you would find them being used as a popular food item in many parts of the world. Squids are also a popular presence in many mythical tales and literature across the world. They can also use ink present in their bodies to distract any kind of predators trying to attack them.