octopus:

The common octopus is not only distinctive for its unique appearance but also for the notable ways it uses to avoid or thwart attackers. This species has a worldwide distribution. It’s abundant within the Mediterranean Sea, the Atlantic Ocean, and Japanese waters.

The common octopus moving through water.

Description

Octopuses vary greatly in size: they’ll age to 12 to 36 inches in length and weigh up to 6.6 to 22 pounds, although averages are much smaller. The skin is smooth. Similar to other octopuses, members of this species have 8 arms that are lined with suckers.

They lack any internal shell and have bilateral symmetry. They are normally ectothermic. This species is believed to be the most intelligent of all invertebrate animals and has highly developed pigment-bearing cells which are individually innervated from the brain. The most appealing feature is that they can change their skin colors to an astonishing degree with great rapidity.

Scientific Classification

Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Octopoda
Family: Octopodidae
Genus: Octopus
Species: O. vulgaris

Habitat

The common octopus is widely distributed in tropical and temperate seas throughout the world. It stays in holes or crevices along the rocky bottom and is reticent and retiring by nature.

Behavior

Octopuses can make discriminations based on visual, tactile, and chemical cues. Octopus vulgaris is normally a solitary, territorial, sedentary, and nocturnal animal. It keeps its home hidden. As fast swimmers, they can jet forward by expelling water through their mantles.

Reef Octopus

Their soft bodies can squeeze into impossibly small cracks and crevices where predators can’t follow and they often protect their homes with shells, stones, and other solid objects they gather. Underwater scrutiny showed that the animals remain in their dens; they leave them at dusk for hunting trips and return at dawn.

Prey and Predators

Octopuses feed mainly upon crabs and lobsters, plankton, gastropods, and bivalves. They also have beak-like jaws that may deliver a nasty bite, and venomous saliva, used mainly for subduing prey. They are fed upon by several marine fishes. They have long been regarded as a culinary delicacy by peoples of the Mediterranean, East Asia, and other parts of the world.

Camouflage

Octopus’s most unique line of defense is its ability to hide in plain sight. By utilizing a network of pigment cells and specialized muscles in its skin, it can almost instantaneously match the colors, patterns, and even textures of its surroundings. Predators such as sharks, eels, and dolphins swim by without even marking it.

A common octopus in hiding.

Breeding

Octopuses have separate sexes, and the male features a specially modified arm, called a hectocotylus, by means of which it inserts spermatophores, or packets of sperm, directly into the female’s mantle cavity. O. vulgaris mates during the winter, and the eggs, about 0.3 cm long, are laid under rocks or in holes.

Baby Common Octopus

The total number of eggs amounts to more than 100,000. Four to eight weeks are required for the larvae to hatch. The female guards the eggs during that time, cleaning them with her suckers and agitating them with water. Upon hatching, the small octopods spend several weeks drifting within the plankton before taking refuge on the underside.

Conservation

Overfishing of these animals can threaten their proliferation. However, presently, they’re not at any specific risk.

BY– Yashashree Kar

20/01/2022