Tuesday, March 16, 2010
The Most Beautiful Yet Deadly Octopus on Earth
From the article on the Environmental Grafitti blog: Beautiful and delicate as the coral itself, the four known species of blue-ringed octopus are largely nocturnal, spending their days nestled like land mines in makeshift nests – usually sea shells, but since the advent of man, these flexible invertebrates have made fruitful use of bottles and also cans. Unlike many sea creatures its size (the largest grow to about 57cm), the blue-ringed octopus has been known to become quite aggressive when its seclusion is disturbed – say, by the foot of a clumsy human. It will retract its arms to make its sharp beak protrude in an attempt to discharge one of nature’s most deadly poisons – the deadly toxin tetradodoxin.
Tetradodoxin is the same deadly ingredient found in the flesh of the pufferfish. In the blue-ringed octopus, it is generated by bacteria that live symbiotically within the host creature’s salivary gland. Following a bite, the toxin will usually kill a human – a being many times the size of the octopus – in a matter of minutes. No effective antidote is yet known. The octopus uses its beak to crack the carapace of crustaceans and the shells of mollusks, afterwards injecting its deadly saliva into the prey’s body. It will suck the soft flesh through the hole it has made, leaving behind an empty shell.
Even amidst the endless variation of the animal kingdom, rarely has death been packaged so attractively. Like many of its relatives in the group Cephalapoda (literally meaning ‘head foot’, due to the apparent body structure of octopodes, squid and others), the blue-ringed octopus boasts a flamboyant colour scheme that changes according to its mood. The meanings of cephalapod colouring are complex and not always well understood, though scientists are slowly coming to the conclusion that they are part of a sophisticated communication system that operates between these intelligent animals.