Tuesday, July 9, 2013

Blue bloods

Octopus have colonized the world, with the ability to survive in water with temperatures as low as 28.8°F (-1.8°C) to more than 86°F (30°C). Michael Oellermann, Hans Pörtner, and Felix Mark of the Alfred Wegener Institute for Polar and Marine Research in Germany have just determined that it is a blue-colored pigment called hemocyanin in its blood which allows the Antarctic octopus to transport the oxygen necessary to survive its freezing habitat. Their hemocyanin is genetically and functionally different from that found in the blood of octopus that live in temperate climates. Because of their limited range, this means that the octopus has a special ability to adapt in order to survive. Oellermann explains, "Octopods are mainly local non-migratory species that move by crawling and have only short life stages in which they inhabit the water column. They are therefore mostly unable to migrate away from or escape 'bad' environmental conditions, which exposes them to higher adaptive pressure to deal with these conditions. Our finding shows a crucial physiological adaption in cold environments that allows octopods to sustain an aerobic life." Meanwhile, scientists have not figured out what biochemical tricks the Antarctic octopus uses to keep its venom working at sub-zero temperatures, so that it can effectively kill its prey. After a 2010 expedition, biochemist Bryan Fry of the University of Melbourne remarked, “Antarctic octopus venom works at temperatures that would stop other venoms in their tracks."

No comments:

Post a Comment

You may add your comments here.