Octopuses are a very successful group of animals — they are found all over the world, and are successful in environments ranging from the relatively warm to the freezing. They’re even found living in regions where the water temperature regularly gets as low as -1.8°C — until now it wasn’t entirely clear what gave them such an impressive ability to thrive in temperatures that low. But now, new research from the Alfred Wegener Institute for Polar and Marine Research in Germany has determined that a great deal of their ability to survive in freezing temperatures is down to a blue colored pigment — known as hemocyanin — that is found in their blood.
For the new work, the researchers compared the properties of the different forms of the blood pigment haemocyanin — responsible for oxygen transport — in Antarctic, Temperate, and Warm-Adapted species of octopods.
“The researchers found that the forms of haemocyanin of the Antarctic octopod Pareledone charcoti, are genetically and functionally different from the temperate and warmer climate octopods, facilitating oxygen release at sub-zero temperatures.”
Michael Oellermann, of the Alfred Wegener Institute for Polar and Marine Research in Germany, stated: “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.”
The new findings were presented at a recent meeting of the Society for Experimental Biology.