Macropinna Microstoma: The Fish with a  See-Through Head

Every once in a while  (well, actually more often  than you might think) nature comes up with something so bizarre  it leaves you shaking your head and  pondering  “How? How? How?” and  puzzling  “Why? Why? Why?”

Found 600m or more down off the coast of California, the species lives in nearly total darkness. A transparent fluid-filled sack replaces the top of the head and two spots above the mouth, called nares, act somewhat like human nostrils, chemically sampling the water.

Experts think the fish hangs motionless in the current with its eyes swivelled upwards to spot the faint silhouettes of its prey. If it spots something it likes the look of, it rolls its eyes back to the forwards position and swims up to intercept it with its small, toothless mouth.

Check it out on this short video clip

Macropinna microstoma A deep-sea fish with a transparent head and tubular eyes

So, what’s the evolutionary advantage of a see-through head?
Would you want one for yourself?
( Might make wearing a beanie compulsory for some of us!)