Toothed whales
Diagram illustrating sound generation, propagation and reception in a toothed whale. Outgoing sounds are
red and incoming ones are greenToothed whales (suborder odontoceti), including dolphins, porpoises, river
dolphins, orcas and sperm whales, use biosonar because they live in an underwater habitat that has
favourable acoustic characteristics and where vision is extremely limited in range due to absorption or
turbidity.
Toothed whales emit a focused beam of high-frequency clicks in the direction that their head is pointing.
Sounds are generated by passing air from the bony nares through the phonic lips. These sounds are reflected
by the dense concave bone of the cranium and an air sac at its base. The focussed beam is modulated by a
large fatty organ known as the 'melon'. This acts like an acoustic lens because it is composed of lipids of
differing densities. Most toothed whales use clicks in a series, or click train, for echolocation, while the
sperm whale may produce clicks individually. Toothed whale whistles do not appear to be used in
echolocation. Different rates of click production in a click train give rise to the familiar barks, squeals and
growls of the bottlenose dolphin. A click train with a repetition rate over 600 per second is called a burst
pulse. In bottlenose dolphins, the auditory brain response resolves individual clicks up to 600 per second,
but yields a graded response for higher repetition rates.
Some smaller toothed whales may have their tooth arrangement suited to aid in echolocation. The placement
of teeth in the jaw of a bottlenose dolphin, as an example, are not symmetrical when seen from a vertical
plane, and this asymmetry could possibly be an aid in the dolphin sensing if echoes from its biosonar are
coming from one side or the other.
Echoes are received using the lower jaw as the primary reception path, from where they are transmitted to
the inner ear via a continuous fat body. Lateral sound may be received though fatty lobes surrounding the
ears with a similar acoustic density to bone. Some researchers believe that when they approach the object of
interest, they protect themselves against the louder echo by quietening the emitted sound. In bats this is
known to happen, but here the hearing sensitivity is also reduced close to a target Enciclopedia libre
Wikipedia
Diagram illustrating sound generation, propagation and reception in a toothed whale. Outgoing sounds are
red and incoming ones are greenToothed whales (suborder odontoceti), including dolphins, porpoises, river
dolphins, orcas and sperm whales, use biosonar because they live in an underwater habitat that has
favourable acoustic characteristics and where vision is extremely limited in range due to absorption or
turbidity.
Toothed whales emit a focused beam of high-frequency clicks in the direction that their head is pointing.
Sounds are generated by passing air from the bony nares through the phonic lips. These sounds are reflected
by the dense concave bone of the cranium and an air sac at its base. The focussed beam is modulated by a
large fatty organ known as the 'melon'. This acts like an acoustic lens because it is composed of lipids of
differing densities. Most toothed whales use clicks in a series, or click train, for echolocation, while the
sperm whale may produce clicks individually. Toothed whale whistles do not appear to be used in
echolocation. Different rates of click production in a click train give rise to the familiar barks, squeals and
growls of the bottlenose dolphin. A click train with a repetition rate over 600 per second is called a burst
pulse. In bottlenose dolphins, the auditory brain response resolves individual clicks up to 600 per second,
but yields a graded response for higher repetition rates.
Some smaller toothed whales may have their tooth arrangement suited to aid in echolocation. The placement
of teeth in the jaw of a bottlenose dolphin, as an example, are not symmetrical when seen from a vertical
plane, and this asymmetry could possibly be an aid in the dolphin sensing if echoes from its biosonar are
coming from one side or the other.
Echoes are received using the lower jaw as the primary reception path, from where they are transmitted to
the inner ear via a continuous fat body. Lateral sound may be received though fatty lobes surrounding the
ears with a similar acoustic density to bone. Some researchers believe that when they approach the object of
interest, they protect themselves against the louder echo by quietening the emitted sound. In bats this is
known to happen, but here the hearing sensitivity is also reduced close to a target Enciclopedia libre
Wikipedia
| Swim and you have a near contact with dolphins, Playa del Carmen is the ideal place for this activity |
Swimming with dolphins:
Playa del Carmen, Quintana Roo, Mexico
Playa del Carmen, Quintana Roo, Mexico
During the Delphinus Trek you will submerge into the
dolphins' world, observing them from a completely
different and unique point of view. Experience the intensity
of their grace and muscular power and watch how they
dive into the water as only a few people have witnessed it.
Delphinus Trek provides you a completely safe
underwater breathing equipment that can be used by any
one.
dolphins' world, observing them from a completely
different and unique point of view. Experience the intensity
of their grace and muscular power and watch how they
dive into the water as only a few people have witnessed it.
Delphinus Trek provides you a completely safe
underwater breathing equipment that can be used by any
one.
If You, or your children wish to swim with
dolphins, to little minutes of Playa del
Carmen is Delphinus, within the park of
Xcaret, where more over to walk and to
enjoy a wonderful day within the park of
Xcaret, You can to swim with the dolphins
and to take a video to take from memory to
house
dolphins, to little minutes of Playa del
Carmen is Delphinus, within the park of
Xcaret, where more over to walk and to
enjoy a wonderful day within the park of
Xcaret, You can to swim with the dolphins
and to take a video to take from memory to
house
Dolphins' echolocation.
Delphinus TREK
Delphinus takes the experience of interacting with dolphins in their natural environment into a new frontier
known as Delphinus Trek.
If being close and touching dolphins seems to you as a unique moment, you can imagine how amazing it can
be to experience this adventure just like a diver underwater, in the most secure way possible.
Delphinus takes the experience of interacting with dolphins in their natural environment into a new frontier
known as Delphinus Trek.
If being close and touching dolphins seems to you as a unique moment, you can imagine how amazing it can
be to experience this adventure just like a diver underwater, in the most secure way possible.
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