Dolphins, Sharks, and Whales: Adventures in Biodiversity

“Space is the last great frontier.”  Space is indeed spectacular, but maybe not the last frontier of discovery, especially when completely new species pop up with some regularity on your own planet.  Due to an inability to grow gills, humans have yet to sprawl into the ocean, so many of these new species are water-dwelling, surprisingly big, and good at hiding.  A few of these new species we are newly distinguishing from their neighbors, and others we’ve just gotten to know.  But these sharks and squids and jellyfish have been here all along, and are now rolling their eyes at the uninformed humans.  Here are some quick introductions to our newly-identified global neighbors.

The half snake, half two-ducks-in-a-costume creature you see waddling around in the video above is a new species of walking shark, also known as carpet sharks.  Named Hemiscyllium halmahera, it was discovered off the coast of the eastern Indonesian island of Ternate, the 16th member of the Hemiscyllium walking shark genus.  This species is a mini version of its relations- on average 12 cm smaller than the 40 cm length of other species- and has distinctive snake-like dark bands running down its back.  The nocturnal members of the genus Hemiscyllium prefer shallow, warm tidal pools, which have one major drawback as a habitat.  As the pools are cut off from the ocean at high tide, any resident Hemiscyllium gradually use up the available oxygen, leaving them in a state of extreme oxygen depletion, known as hypoxia.  They have evolved to survive until the tide comes in by carefully regulating blood flow, even ‘turning off’ – reducing the metabolism – of some areas of its brain.  For an animal that looks like a cartoon creature come to life, that’s quite a talent.

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