Ultrasonic Communication

It is a well known fact that bats "see" with ultra-high frequency sound; and while there are many bats who also see quite well with their eyes, it is their precise use of echo location that distinguishes these remarkable creatures.

The accuracy of their skill allows them to feed on moths, mosqitoes and other flying insects at high speeds and in the dark. Some species of bats have refined this perception so well that they can fly through mazes of wires as thin as a human hair. There is even a species of fishing bat that can single out a small fish underwater solely on the reflections of ripples left by the fish on the water's surface.

The upper ranges of sound perception are not just reserved for bats. It is no surprise that many insects have developed hearing in this range to warn them of incoming bats. And in a survival strategy only recently exploited by sophisticated defense technologies, the Tiger Moth has learned to instantaneously mimic back the echolocation calls of predatory bats - confusing them as to the whereabouts of their target.

We know that dogs and cats can hear sound far above our human auditory frequency range; and while they don't produce ultrasonic sounds, it is likely that they use them in locating their prey - mice, birds and small rodents that do produce these sounds.

The mockingbird and even the common house sparrow do have ultrasonic components to their song. They may use these sounds to announce their presence to the other birds in their community. In a stunt trypical of the mischevious nature of the mockingbird - but remarkable in execution, involved a friend who had installed an early model garage door opener that worked on ultrasound. The neighborhood mockingbird was quick to pick up on this fact and would revel at opening and closing the garage door throughout the day. Garage doors are now operated by radio frequencies - likely as a response to this problem.

One of the advantages of ultra-sonic sound, as opposed to the sound that we can hear - is that the tiny wavelengths of these high frequencies can penetrate into and reflect off of the smallest crevice and contour, echoing a sound profile of minute detail. These sounds can even be used to probe soft tissues, reflecting the differences between bone, flesh and blood. Our physicians use this feature to gently explore the contents of a mother's womb to determine the health and identity of her child.

We are not the only animals to use ultra-sound in this way; while swimming with dolphins many women have had their pregnancies announced by the particular care shown them by these sensitive creatures. It seems that the dolphins can see a foetus within a mother's womb even when very small. It is probable that dolphins use these sounds when hunting to identify the soft and vulnerable areas of their fast swimming prey - the more likely to assure a clean, tasty kill. There is also a distinct possibility that dolphins use these sounds to communicate.

Psychologist John Lilly studied dolphins to determine how they communicated the structure of their complex community to each other - how they were able to coordinate advanced hunting and play strategies, often a high speeds. He spent 18 years performing repetitive routines with them; recording all of their sounds in an attempt to learn their vocabulary. Not once in that time did they repeat a sound phrase - at least a phrase they were not asked to repeat.

We know now that not all communication requires a symbolic vocabulary - that many deeper messages are imbedded in the tone of a voice or the turn of a phrase. But the degree of accuracy conveyed in dolphin communication indicates the possibility of an astounding form of communication - communication through sonic holograms.

It is clear that the dolphins - like the bats, can perceive complex objects through "sound pictures" reflected back at them; that the sound signals echo precise and distinct profiles of the objects in their sound horizon. It is also possible that dolphins may be able to project these sound pictures to each other - that instead of saying "fish" or "tuna" that they could project an image of these things - placing them in strategic context to allow the receiver to know what to do.

This form of communication would permit a very rapid conveyance of complex information. A whole situation could be illustrated with a short series of squeaks and clicks. This also opens up fantastic possibilities for play; when any object of the imagination could be instantaneously manifest in a living space.

Had we this ability this whole narrative might have been presented and understood within the time I took me to speak the first paragraph.