Fish funnel their food with jets

Unlike humans, many fish grab their food by sucking up the water that surrounds it. Once sucked into fish's mouth, then gets swallowed up. What of carried it there? The simplest way for to exit is across gills, but if just followed suit, would be inhaling and spewing out through gill slits. Pauline Provini, from Département Adaptations du Vivant, Paris, France, wasn't convinced this most elegant option wondered whether independently filter away water. Together with Alexandre Brunet, Andrea Filippo Sam Van Wassenbergh, they set see what goes on inside a mouth while eating.As it's not challenging enough Provini colleagues needed how swirl around inside; hard persuade say ‘ah’ take peek. As next best thing, team used fluoroscopy – moving x-rays happens mouths two kinds fish, carp tilapia, multiple angles. It's about using alone, so metal markers, which show really well x-ray images. First, implanted pellets small beads. Next, flow water, crafted an armada miniscule floats, encasing 0.4 mm long rods in tiny foam life jackets. These drifted waiting taken hungry when food.The researchers found expandable create spout fast-flowing fluid funnel shifts down centre front back. had before was case, now seen first-hand. Pieces hitch ride jet and, instead being belched slits, are entrance oesophagus, muscular tube leads stomach.But story doesn't end there. synchronised movements jaws throat waft back forth little form rhythmical gargling. suggest ability extend consideration gave sample sift tastiest morsels, rejecting unpalatable scraps.In addition, saw floats swirled edges fish’s without single one ever getting swallowed. Astonishingly, managed avoid swallowing any mistake. Far messy eaters, seems these have impeccable quite particular table manners.