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Social Intercourse and Communication
- Social Intercourse and Communication - With Other Dolphins
- Social Intercourse With One Another
- Communication With One Another
- Social Intercourse and Communication - With Humans
- Social Intercourse With Humans
- Communication With Humans
Social Intercourse and Communication - With Other Dolphins
Social Intercourse With One Another
Dolphins live in groups. Social intercourse with one another is similar to that of humans. They are attached to each other and live together as a family.
Sociability for dolphins is not the main reason to live in a big group. It is also a certain form of security which they do not have as induviduals but do have as a group.
|One of the security reasons is the younger generation. Until they are about two years old they are protected by their mother. If the mother needs to search for food, one of the aunts takes over the nursing. They do this by swimming in between the mother and the offspring. When the mother returns, she takes back her offspring in the same way. Good communication is essential for young dolphins, and it is for their own security.|
|The search for food also takes place in a group. They will surround a large shoal of fish and feed one by one. They do this by swimming 'straight up' in a circle around the fish. If the dolphins are selfish or if they do not cooperate, then the feeding will not be successful.|
|Another advantage of working in a group is that the dolphins will be able to defend themselves much better. Because of their excellent swimming and the high speed they go at (40 kilometers per hour), they can even challenge a whale. They have a very hard nose to attack and to batter the enemy. As an extra weapon they have sharp teeth, and a strong tail with which they can hit hard. A shark probably could not win against a couple of dolphins. Another question immediately comes to mind - will the dolphins use these weapons against one another? The answer is yes, because like us they have rows once in a while. One of the causes can be a female dolphin, or simply just irritation. Most dolphins have a somewhat battered skin (well seen in closeup), which is mostly caused by another dolphin.|
Living in groups provides warmth and comfort to the dolphins. Dolphins (again like people), enjoy each other's company. Playing is part of their daily life. They prefer playing together, but they know quite a few individual games. One of these games is swimming. They like jumping high up out of the water and they also do the craziest things under water. They make air rings out of air with their blowholes, which they then try to keep these air rings under water. (More information about this is found in the next section: 'Playfulness') You can also view a few videos in this section.
Another interesting fact of the dolphins is concerned with sleeping. Dolphins can never fall asleep completely, as they would drown if they fall into a deep slumber. How do dolphins then get their rest? They only rest half their body at a time. Dolphins have the option of putting one half of the brain to rest, while they swim around and breathe by using the other half. You can tell very easily when they sleep because one eye is clearly closed. If they occasionally put either half of the brain to rest, they rest completely.
One would not guess it, but dolphins like 'chatting' to one another. People working with dolphins sometimes see two dolphins having a big discussion.
Communication With One Another
Dolphins can communicate with one another by using very high (ultrasonic) sounds. The hearing of dolphins is much more sensitive than that of humans. It can detect sounds up to the frequency of 200000 Hertz (vibrations per second). This is very high in comparison to our hearing. (up to the frequency of 20000 Hertz) Dolphins can thus produce sounds that are way too high for us to hear.
This high frequency also has advantages for orientation. The ultrasonic sounds are echoed and that is how they can locate objects (or prey) in the dark. Dolphins can be disturbed by other (high-frequency) sounds in the sea and sometimes they lose their orientation completely because of this. The consequence is often read in the papers or seen on television, the dolphins can accidentally be washed ashore. (More information in the 'Navigation and Echolocation' section)
Social Intercourse and Communication - With Humans
Social Intercourse With Humans
As it has been said already, dolphins like to play. They search for a good friend to play with. You often see that dolphins try to swim along with boats, or that they go to shore where there are people. People are also sometimes saved by dolphins, when they happen to drown. Why is it then, that dolphins seemingly enjoy being with humans?
For many people including scientists (biologists), the exact reason is not known. Most people say that this is just playfulness. There have been observations of dolphins bringing mattresses and pieces of wood ashore. This makes the argument of "dolphins save drowning people" invalid. Furthermore it has been proved that dolphins like to play, and people are treated as nice toys by dolphins. This is probably also the reason for the fact that dolphins enjoy social intercourse with people. (Read the 'Intelligence and Language' section)
Dolphins are eager to learn. Just like dogs, dolphins are easily trained for appearances. This is usually not against their own will. Some dolphins, when given a ball, keep it because they like it so much. Humans are not only nice toys, but they also make a lot of things which increases the pleasure for the dolphins. We as humans also make use of this by putting them in dolphinariums where they do shows, because we, on the other hand, also see dolphins as toys.
The social intercourse between dolphins and human beings is reasonably good and flexible, but we, like humans and dolphins among themselves, have rows once in a while. These are often flaws in the communication, about which I'll tell you more in the next section.
Communication With Humans
Communication between dolphins and people is dificult. We have a competely different language and dolphins do not have vocal chords. Dolphins communicate using extremely high pitch sounds via the blowhole, which we are unable to hear. Humans have developed appliances - which dolphins incidentally aren't able to do - that produce and pick up these sounds. There are a lot of biologists deciphering the language, but this has only succeeded to a small extent. The dolphins in a dolphinarium know various signs and these signs are the main means of communication. The movements of a dolphin give humans some clue as to what they mean. This is the case with attendants or other people who have a lot to do with dolphins.
There is another problem with communication. Dolphins do not have facial expressions. They always have the same pleasant smiling snout, even when they are angry. Futhermore, they don't show a lot when they are angry. If you want to swim with dolphins without creating any problem, you should attend a course on safety. There have been cases where swimmers have been attacked by dolphins because of miscommunication.
"Dolphins and Whales (14)," Encyclopedia Grzimek (1974),
Vol. 11, page 506 - 570.
Encyclopedia Grzimek (1974),
Vol. Behaviour, page 49, 147, 156, 218, 221, 320.
Toinny Walet Lukken. Personal Interview. 15 June, 1998.