As an obligate ram ventilator, a whale shark must continuously swim or die.
Sharks must constantly swim or they'll die, right? Actually, this tale isn't true for all shark species.
Like other fish, sharks "breathe" through their gills, which are respiratory organs akin to our lungs. As water passes over the gill's membranes, tiny blood vessels extract oxygen from the water. Carbon dioxide waste also passes from the shark's blood and out of its body through the gill tissue.
But just how the sharks force water over their gills differs among species.
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