As NASA’s Dawn circles Ceres in search of oceans which could harbor life, it’s worth noting that much of Earth remains to be fully understood. But new research published in Frontiers in Zoology promises to answer at least one of our many questions: how can an Antarctic octopus survive waters cold enough to kill humans in seconds?
The answer lies in their blue blood.
Moving oxygen through the body doesn’t work well in lower temperatures. The cold causes our blood to thicken, and oxygen diffuses at a lower rate. In short, the colder the temperature, the harder it is for your body to breathe.
Still, one thing cold water has going for it is an already high level of dissolved oxygen, and many octopods’ blue blood pigment, haemocyanin, allows the creatures to utilize this available oxygen and transport it through the body.
“This is the first study providing clear evidence that [haemocyanin] undergoes functional changes to improve the supply of oxygen to tissue at sub-zero temperatures,” the reports lead author, Michael Oellermann, said.
After studying the blood of the Antarctic octopod Pareledone charcoti, researchers found that the species contains 40% more haemocyanin than other species. The study says that these high concentrations make up for the pigment’s weak ability to deliver oxygen.
What’s even more impressive is the fact that while the Pareledone thrives in its freezing environment, its blue blood works even better in warmer temperatures. Researchers tested the octopi in water that measured 0 degrees Celsius, as well as water measuring 10 degrees Celsius.
Meaning its adaptive blood could improve the Pareledone’s chances of enduring a heating planet.
“…Due to improved oxygen supply by haemocyanin at higher temperatures,” Oellermann said, “this octopod may be physiologically better equipped than Antarctic fishes to cope with global warming.”
Life, as the saying goes, does indeed find a way.
