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New research on an unusual organ in the jaws of rorqual whales --better known as filter-feeding whales -- offers new insight intohow such a large mammal is able to subsist on such a small diet. Of course, "small" when it come to whales means the size of thefood, not the quantity. Indeed, many rorqual whales -- whichinclude humpbacks, the endangered fin whales, and the blue whale,largest animal on earth -- can consume several tons of krill everyday, using their baleen. The secret to their success is something called "lunge-feeding," inwhich they open their massive jaws, exposing the baleen and fillingtheir mouths with immense quantities of water -- tens of thousandsof gallons -- and anything edible therein. According to the New York Times , the unique feeding process is the result of an organ in thewhales' lower jaw, which allows for an expansion of theaccordion-like jaws, filling with water like the pouch of apelican's beak before pushing the water back out and retaining thefood left behind. A new report published in the journal Nature says that the organ iscrucial to coordinate the physiological processes behind filterfeeding. According to the BBC , previous scientists had possibly dismissed the organ as beingnothing more than a fluid filled sac. One scientist who helpedauthor the new study referred to the organ as little more than a"gelatinous mass." The research was conducted on dead fin and minke whales caught byIcelandic whalers. Whales are able to expand their jaws to contain such huge amountsof water because their lower jaw isn't fused -- in the way humans'jaws are. Instead, there are two separate bones, with thenewly-discovered organ located at the front tip of the mouth in thegap between the bones. So how does the organ work? According to the Los Angeles Times : (The organ) is composed of connective tissue with protrusions thatcontain nerves, and is suspended in a gel-like material. Theevidence indicates that the sensory organ responds to jaw rotationwhen the whale opens and closes its mouth and when the whale'sthroat pleats expand as it takes in water. "This odd arrangement of tissues didn't make much sense to us atfirst, but then we realized that that this organ was perfectlyplaced, anatomically, to coordinate a lunge because the softstructure is pinched by tips of the jaws and deforms through thecourse of a lunge," (study author Nick) Pyenson said. "Thisdeformation is registered by nerves inside the organ, informing thegulping whale about its gigantic jaws, which must close before preyescape." The result, Pyenson said, is a controlled lunge where the whaleadapts to the way the water fills its mouth, rather than just ablind lunge that ends when the whale's mouth is full. The finding is particularly unique since humans -- scientists,whalers, and subsistence hunters alike -- have been butchering anddissecting whales for years, and no one has noticed the amazingorgan before. Read much more about the new discovery at the New York Times , the Los Angeles Times and the BBC . We are high quality suppliers, our products such as Polyester Nonwoven Fabric , Non Woven Garment Bag Manufacturer for oversee buyer. To know more, please visits Agriculture Nonwoven Fabric.
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