> i am 12 years old.I have studied whales for 7 years and plan on becoming
> marine bioaligist but i have noticed i have never seen enything about the
> difference in whale vocal cords i would like to know because i need to know
> for a science fair for a totally never used science project
> Reply: Dear Asia,
> Whales don't have vocal cords like we do, but they appear to have membranes of
> similar form which may serve the same purpose as vocal cords. They produce
> sounds by forcing air from their nasal passages into sacs, without exhaling
> any air. It is believed the sounds are made in the throat or larynx. After
> taking a breath of air, they can reuse that air several times to make sound
> before exhaling it.
> Whales also use a mechanism called echolocation to 'see' with their ears.
> They direct a beam of click-like sounds and listen to the echoes that return
> from objects in the path of the sound. If you direct a flashlight at
> something in the dark, you illuminate the object with light and you can see
> it. Whales can 'illuminate' a silent fish with sound in order to 'see' it.
> From the returning sound, the whale learns the size, shape, speed, and
> direction of the subject. Dolphins can even beam their sound waves into mud
> to find hiding fish! (Seawater and flesh have approximately the same density,
> so the sounds whales emit penetrate the flesh of submerged animals. It has
> been suggested that whales can actually see the inside of their companions and
> their prey. The resulting image might look like an ultrasound picture). Fish
> can't hear the high pitched sounds, so they don't realize they are being
> looked over. It has been postulated that some cetaceans, such as the sperm
> whale, may even use strong pulses of sound to stun their prey!
> Toothed whales generally spend most of their time in shallow, coastal areas
> and use sharp, high frequency sounds that don't travel very far through the
> water before being converted into heat. Short, high-pitched, rapid sounds
> used on objects in close proximity allow whales to hear the finer details.
> Some types of baleen whales (like blue and fin whales) spend a lot of time in
> deep, dark waters and use loud low frequency, long-ranging sounds to
> communicate and navigate the seas. Low frequency sound can travel for long
> distances, but only gives broader details. The distance traveled depends
> largely on the depth and temperature of the ocean the sound is sent from
> (temperature and pressure change the conductive properties of water).
> Fin and blue whales are examples of loud-voiced whales. They are larger
> baleen whales that are found in all oceans. While humpback, right, bowhead,
> and gray whales have specific breeding grounds, so far no one has found a
> breeding ground for the rorquals other than the humpback. Fin and blue whales
> may not need a distinct breeding ground. They may just start calling with
> their loud, low songs to potential mates. These calls can travel for hundreds
> and even thousands of miles away. It is not out of the question that the
> calls may also contain information about where food is.
> Humpback whales make rhythmic, repeated patterns of sounds, or songs. Their
> songs (sung mostly by males) seem to be related to mating and may function the
> same way bird calls do; as a challenge by males to other male rivals and as a
> means of attracting females. Suspended head down in the water, very still,
> humpbacks can sing for hours. All humpbacks sing the same song on the same
> breeding ground even if they are very far apart. The lowest sounds in their
> songs are audible over long distances.
> Other possible forms of communication that whales employ are breaching,
> lobtailing, and flipper slapping, which may be ways of sending sounds intended
> as communication at short range through the water. They could be saying, "I'm
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