October 8 marks the International Day of the Octopus, kicking off in Octo style as part of the first day of the International Cephalopod Awareness Days, that ends on October 12.
These solitary creatures, called Octopuses (and not octopi, contrary to popular belief), belong to the order Octopoda, comprising of over 289 different species.
Collectively, it makes up for one-third of the total number of cephalopod species, grouping up with their cousins, the squids, cuttlefishes and nautiloids. They belong to the family of invertebrates known as Molluscs.
The common octopus (Octopus Vulgaris) is spotted frequently across the Maldives. ‘Boava’ as it is known in the local language, is widely regarded as a great delicacy by the Maldivian people.
Most octopuses belong to the suborder Incirrata and are entirely soft-bodied with no internal skeleton or protective shell. A beak in the similar form of a parrot’s beak is their only hard part. This allows them to squeeze through crevices and holes roughly the size of a quarter, only limited by the size of their beaks.
Octopods have a relatively short life span, some species living for as little as six months, though larger species on the Octo scale such as the North Pacific Giant Octopus, may live up to 5 years under a suitable environment.
According to National Geographic, a study revealed that all octopuses, cuttlefish and some squid are venomous, but the only threat to humans come in the form of the tiny but fatal blue-ringed octopus.
This highly intelligent animal has over 500 million neurons located mostly in their arms, spread over the nine brains encompassing its body. In fact, Octopuses are widely considered to be the most intelligent of all invertebrates.
Octopuses have three hearts. Two pumping blood through each of its two gills, while the third pumps blood throughout the body. Octopuses have evolved to use a copper-rich protein ‘hemocyanin’ for transporting oxygen. This copper-based blood is more efficient in colder temperatures and water with low oxygen levels.
Reproduction, however, revolves around death for these eight-armed creatures, with the male living for a few months after they mate; while the females, on the other hand, die shortly after their eggs hatch, as they neglect to eat during the one month period they spend caring for her unhatched eggs.
The male octopuses have a specialized arm called a ‘hectocotylus’ to insert spermatophores into the female’s mantle cavity. Some species of female octopus can keep the sperm alive for weeks, before fertilizing her eggs. The female can lay approximately 100,000 eggs, capable of producing a litter of roughly 80 juvenile octopuses.
These eight-armed animals have a few tricks up their sleeves to help defend themselves. If found under duress, octopuses shoot an inky fluid from their body distracting and confusing the aggressor. They can also hide and blend in with their surroundings, too, by changing their specialized skin cells, called chromatophores, for both colour changing, light reflection and refraction. They also utilize this ability to communicate with and warn other octopuses.
Octopus fossils have dated back more than 300 million years, and predate the existence of dinosaurs. That is how cool they really are.
Although octopods are not considered endangered, like many of their marine counterparts, they face significant danger from human activities such as habitat destruction and reduction of available food due to overfishing and marine pollution.