Hold onto your breath, dear readers, for this month we’re diving deep. Hundreds of metres beneath the surface of the world’s oceans, there lives a curious fish that waddles along the seafloor using its fins like four little legs. It has a pink complexion and a frog-like mouth. Upon its head is a unicorn-like dorsal fin which glows in the dark and entices inquisitive fish to their doom. This is the pink frogmouth, a deep-sea creature that looks to have been designed by a sugar-addled six-year-old.

Still holding your breath? Good. You and the pink frogmouth have this in common. Earlier this year, scientists discovered that this fish (and other members of its taxonomic family) has the unique ability of holding its breath underwater, for as long as four minutes.

Fish breathe by swallowing oxygen-containing water and pumping it through their gills, where the oxygen is extracted. The pink frogmouth, however, is able to hold this water in its gill chambers without exhaling. Puffed-up like this, its body volume can increase by as much as 30 per cent. There are a couple of possible reasons for this unusual behaviour: it could be a way of saving energy in an environment that’s lacking in prey, and it could also help to ward off predators, similar to the pufferfish’s defence mechanism.

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Jules Howard is a zoology correspondent, naturalist and author of more than 10 books including The Wildlife Pond Handbook. He writes for a number of publications including The Guardian, Science Focus and BBC Wildlife Magazine.