One of the closed book of marine beast is how they discover their way around in a world with no landmark . Many sharks , for instance , live in the oceanic geographical zone — the part of the ocean that ’s neither near the seafloor nor any seeable shoreline . So how do they navigate , reliably transmigrate to the same place year - to - year ? ( One pop annual gathering shoes between Baja California and Hawaii has been likened to aBurning Manfor great White . ) They use their sentience of olfactory perception , accord to a new study in the journalPLOS ONE .
Sharks practice their sharp horse sense of smell to do more than find their way to a wounded seal , according to research worker led by University of California San Diego shipboard soldier life scientist Andrew Nosal . The researchers captured 26 leopard shark off the seacoast of San Diego and inserted crude oil - jelly - covered swabs into the naris ( the shark rendering of a anterior naris ) of 11 sharks . As a controller , the team mimicked put in cotton into the nares of the continue sharks but did n’t actually insert any cotton wool . Then , using a tank that blocked the sharks from seeing or from sensing charismatic fields that might guide them , he transported them an hour northwest and free them with rag and sensors attached to them to dog their movements . He also captured and released 10 sharks on a different Clarence Shepard Day Jr. without intervene with their senses of olfactory perception .
He plant that shark that could n’t smell swam slower and did not drop as much time swimming toward shoring as the control shark . The sharks that had no wool shoved up their noses swim very quickly in straight way of life back to shore , while those that could n’t smell appeared disoriented . Their paths approximated a “ random walk , ” according to the study , though they did incline towards heading for shore , suggesting that they might have gotten there finally . Nosal and his team suppose that the shark might be smelling chemical associated with chlorophyll that live in greater quantities nearer to the coast in California .
[ h / triiodothyronine : Popular Science ]
