Let’s get cirri-ous: an acorn barnacle’s feathery phalanges are foolproof for filtering a feast from fast flows! These captivating crustaceans do a little headstand when they’re but wee plankton settling down, cementing their noggins to the seafloor before forming a shell around them. By flapping their feet in the current, those tiny toe hairs, called cirri, trap detritus and plankton as they pass by. Once a snack is secured, the barnacle pulls its legs inside, scrapes off its filtered fare and