Blue-Ringed Octopus Essay
The blue-ringed octopus lives in shallow reefs and tide pools in the Pacific Ocean, usually at depths ranging from 0 to 20m (Sheedy and Beasley, 2003). There are four kinds of blue-ringed Octopuses (genus Hapalochlaena): (1) the greater blue-ringed octopus (Hapalochlaena lunulata); (2) the southern blue-ringed octopus or lesser blue-ringed octopus (Hapalochlaena maculosa); (3) the blue-lined octopus (Hapalochlaena fasciata); and (4) Hapalochlaena nierstraszi, first described in the year 1938 from a single specimen found in the Bay of Bengal (Blue-Ringed Octopus, 2007).
The blue-ringed octopus uses its dermal chromatophore cells to camouflage itself until it is provoked. Before it is provoked, its color may vary from dark brown to dark yellow (Interesting Animals). Once provoked, the octopus swiftly changes its color to bright yellow with either blue rings or lines. The blue-ringed octopus typically hunts small crabs, hermit crabs, and shrimp. In addition, the octopus is ever ready to bite its attacker if provoked or stepped on (Blue-Ringed Octopus).
Although it grows to a maximum length of 200mm when its body is totally spread out, and usually appears to be about the size of a golf ball, the blue-ringed octopus may kill a human being with a bite within minutes (Sheedy and Beasley). The human being bitten by a blue-ringed octopus does not feel pain. Rather, he or she would first feel nauseous. At the same time, his or her vision would become hazy. After a few seconds, the individual would turn blind. He or she would also lose the sense of touch, besides becoming unable to speak or swallow.
Three minutes later, the human being is expected to turn paralyzed, and become unable to breathe (Interesting Animals). BLUE-RINGED OCTOPUS Page # 2 The poison of the blue-ringed octopus is contained in its saliva. The saliva comes from two glands, each of which is as big as the brain of the octopus. Poison from one of the glands is used on the main prey of the blue-ringed octopus – the crab.
This poison is relatively harmless to human beings. The poison from the second gland is the truly harmful one, containing some maculotoxin which is a neurotoxin that can prove to be stronger than the venom of all animals found on land. The venom also contains 5-hydroxytryptamine, hyaluronidase, tyramine, histamine, tryptamine, octopamine, taurine, acetylcholine, and dopamine; and is 10,000 times more potent than cyanide (Blue-Ringed Octopus; Sheedy and Beasley). This poison, of course, serves as a defense against predators.
The blue-ringed octopus is known to either secret its poison in the vicinity of the prey, wait until the prey is immobile before it devours its prey; or simply jump out and envelop the prey in its tentacles and bite it (Interesting Animals). The most poisonous octopus in the world is a soft-bodied organism. Also like the rest of the octopuses in the world, it has eight arms or tentacles (Interesting Animals). The blue-ringed octopus lives in crevices or holes; burrows as a means of gaining protection; and advertises its toxicity when provoked like all other octopuses.
What is more, the blue-ringed octopus hatches from an egg (one of 60-100 at a time) and is approximately the size of a pea at the beginning of its life. This octopus grows and matures rather quickly until it reaches its adult size. Its life expectancy is around two years (Sheedy and Beasley). BLUE-RINGED OCTOPUS Page # 3
References 1. Blue-Ringed Octopus. (2007, March 11). Wikipedia. Retrieved from http://en. wikipedia. org/wiki/Blue-ringed_octopus. (15 March 2007). 2. Interesting Animals. Did you know? Retrieved from http://www. didyouknow. org/index. html. (15 March 2007). 3. Sheedy, John, and Same Beasley. (2003, April 1). The Blue-Ringed Octopus. Earlham College. Retrieved from http://www. earlham. edu/~sheedjo/blue-ringedoctopus. htm. (15 March 2007).