Nathan Cummings, age 15, of Camden, N.J., for his question:
WHAT IS COMPARATIVE PSYCHOLOGY?
Comparative psychology is the psychology of animals. It is the study of animals' intelligence, needs, sensory capacities and characteristic ways of behaving.
Animals are studied in their natural environments and in such special environments as laboratories and zoos. The natural environment is of the most interest since animals are equipped by nature to survive there.
Scientists study animals because of curiosity about them and also for practical reasons. For example, information about the migration and spawning of salmon is not only interesting in itself, but it is also good to have this information for economic reasons.
Experiments with animals also give information about man under conditions in which human experimentations are not practical. The brains of rats, for example, can be stimulated with electrical currents passing through fine wires embedded in the brains by surgery. This type of experiment has yielded much information about how the brain regulates such basic drives as hunger and thirst.
Experiments with rats have also provided a great deal of valuable information about the psychological effects of drugs.
Results of animal experiments can be applied to man only if it can be assumed that experiments with human beings would yield the same results. Whether they would or not is uncertain. The assumption that they would can be justified sometimes because of the structural resemblance between man and the higher animals, and the similar results of experiments that can be performed with both man and animals.
Comparative psychologists have learned a great deal about man through the study of animals.
Comparative psychologists are particularly interested in the ability of animals to learn about their environments and discover new ways of dealing with them.
Comparative psychologists have discovered that the intelligence of an animal is closely related to the structure of its brain. Environments change and some animals adjust more easily than others to these changes.
Some of the most penetrating insights into the behavior of animals have been achieved by making radical changes in their natural environments. For example, rearing a chick in complete isolation, comparative psychologists have found, shows that social stimuli are necessary for its normal development.
It has been found that a jellyfish is incapable of learning. The behavior of this animal is determined entirely by its inherited structure. If that behavior is not appropriate to the environment in which the jellyfish finds itself, the animal simply will not be able to survive.