Tooters and Shakers
There’s certainly no doubt that something as big as an elephant would have no problem alerting others to approaching danger. All it has to do is raise its trunk and trumpet! But wait a minute- what’s all that stomping about?
Research conducted by biologists in Namibia and at the Oakland Zoo in California has substantiated the fact that the stomping of African elephants creates vibrations of a certain frequency detectable by other elephants, even at a distance. Upon reception of these low frequency vibrations in their feet, the elephants react by crowding together defensively or by altering their position so as to better receive the message.
The precise mechanism by which the elephants receive these signals is still ambiguous, however. Having observed elephants spreading their ears forward close to the ground, biologists suggest the role of enlarged earbones. In addition, the knowledge that elephants have nerves in their toenails elicits the hypothesis of sensitive nerve endings in the feet.
These amazing stomping signals can travel up to 20 miles in the ground; however, the animals also make vocalizations of low frequency that carry through the air and cause corresponding vibrations in the ground. Long, loose vocal cords in the larynx serve to lower the frequency of vocalizations below the hearing of many other animals; the mouth, trunk, and pharyngeal pouch aid in resonance. Although the airborne signals are faster, they travel only up to 6 miles, while the accompanying seismic vibrations travel almost twice as far. Presently, about 70 calls have been identified, most of which are made by females although young elephants do have special calls of their own.
Elephants are not the only animals that use seismic pulses to communicate. Fiddler crabs use their claws to bang out signals of territorial warning. Scientists hypothesize that these vibrations may be used for location of potential mates, migration, and warning purposes.
While this is a fantastic phenomenon used extensively in the animal world, don’t do it at home!
Posted by J543
posted by PWH @ 5:40 PM
6 comments
6 Comments:
This is an interesting fact about elephants. This was actually discussed in our biology text book, and I was wondering if there was more information about it. Its very interesting that the sounds are produced via airwaves AND vibrations in the ground. 6 miles is still a very large distance for a sound to travel. And the vibration part is just phenomenal...20 miles! Eventually maybe we will understand exactly how this works, as it might be able to help in the hearing aid industry perfecting their products to pick up sounds, or maybe even sense vibrations of other individual's larynx!
I've read other articles about this topic of elephant infrared like sound waves being passed on to each other via vibrations in the earth and sound waves at lower frequencies then humans can hear. This discovery intrigued me because it helps explain the behavior of the animal, and shows how that animal can communicate with others. I liked how there was more than one example of seismic vibrations given it shows how evolution similarities between different animals.
These ideas were presented in the sensory chapter of the textbook for Biology 101. One major contributor to the elephant's ability to pick up seismic activity in the ground may be the enlarged surface area of the pads on its feet. This is a very interesting concept, in contrast with the opposite end of the sensory spectrum for sound, whereas bats and dolphins use ultrasonic waves to communicate and travel, it is more than likely that an elephant would use infrasound to communicate through the air as well as vibrations in the ground that are picked up by nerves in their feet. This is comparable to the concept of animals that can see ultraviolet light (i.e. birds) and others that can sense infrared waves (i.e. the pit viper). With that in mind, its more than likely that an elephant can sense seismic activity and also create it.
buabbud6
This is a very intriguing! Can elephants decipher between various vibrations and vocalizations caused by different animals or natural occurrences (thunder, earthquakes)? Or do they get confused and thrown off easily by signals that are not from other elephants? How do the vibrations and vocalizations differ according to sex, age and population? And how many different messages can be transmitted? Do their trunks help in receiving signals? And what other adaptations have elephants evolved for communication besides enlarged ear bones and nerves in their toenails? Great job!
I find it interesting how different animals have their own ways of communicating with each other within their own species. Is it possible for other animals to detect the elephants stomping or low frequency vocalizations? If so, how does it affect the elephants and the other detecting animals' responses?
Robyn Botelho
I really enjoyed this article! It goes to show how much we still have to learn about our world and its inhabitants. Elephants have the unique ability to hear through the nerve endings in their feet and enlarged ear bones. I find it hard to imagine having better a different level of hearing than what we have as humans. It’s amazing to think the diversity evolution has created in animal senses.
- deae6
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