Underneath the ice, spikes meet spikes as an Alaska king crab the size of a nickel crawls over a knobby sea star. After a dozen years, the crustacean will grow to the size of a tractor tire. Photograph by Brian Skerry
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Underneath the ice, spikes meet spikes as an Alaska king crab the size of a nickel crawls over a knobby sea star. After a dozen years, the crustacean will grow to the size of a tractor tire.

Photograph by Brian Skerry