Our photo of the day, taken by underwater photographer extraordinare John Turnbull, comes from Bare Island, Australia. The striped catfish Plotosus lineatus is showing off some mighty whiskers, which inspire the question: Why do catfish have them in the first place?
Called barbels, the whiskers of a catfish are not like the whiskers of its mammalian namesake. The fish version are more skin than hair and come complete with chemical receptors enabling the catfish to smell and taste with them. Maybe if catfish didn't spend so much time in muddy bodies of water – where visibility is low and smell and taste are king – they would not have developed these odd little appendages that let them find food in the murk. But thankfully, it didn't turn out that way.
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