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It is highly visible and hugely iconic.

But just as the tiger and the rhinoceros depend on creatures you cannot see without a microscope and would not willingly give house room to if you could, so does the polar bear stand, literally, on a patchwork lattice of invisible, miniscule life.

Life-forms such as polychaetes (or bristleworms), copepods and amphipods that live just under the ice, around its edge, or even inside the floes themselves.

"There are polychaetes, for example, which have juveniles or larvae that instead of living in the water column as they usually do, they go into the ice," Bodil Bluhm relates.

"And the sea ice consists of crystals, of course; and between the crystals, there's a liquid network of brine channels, and this network houses algae, and the ice algae are abundant at a time when the water column has very little food."

The channels are a good place for the larvae to find food, and also to hide from anything that might want a polychaete infant for dinner.

The significance for things that you might care more about?

In a nutshell, the vast and complex food web that spans the Arctic; from the centre to the continental shores, the floating ice down to the vast seafloor canyons, the insignificant algae to the majestic top carnivores.

Temperatures are rising faster in the Arctic than just about anywhere else on Earth. If you want to understand how that will affect life we can see, you have to know what it means for organisms like the polychaete larvae.