Connect to these sites:
Anorexia and Bulimia Association site
Aphrodisiac page
|
Although humans and other primates can be ready for sex at virtually all times, among most lower animals sexual activity is motivated largely by hormones (from ovaries or testes) plus instincts. Most commonly, when the female ovulates, her sex glands release the hormone estrogen into the bloodstream, making her sexually receptive during the period referred to as estrus.
Courtship in animals is the behavioral process whereby sexually mature individuals of a species become mating pairs. Often sensory cues in courtship attract a potential mate. Chemical odor cues often serve as sexual attractants in animals. Pheromones are chemical substances secreted by an animal that are used in communication with other members of the same species. We know that pheromones play an important role in the sexual behavior of lower animals. For example, the female cockroach produces a pheromone that attracts males from great distances. As the male cockroach approaches and his antennae touch the female, he begins to exhibit precopulatory behavior. Among mammals, many males have scent glands that secrete pheromonal substances that attract females. For instance, deer rub their hind legs, which contain scent glands, against trees, and urine from female dogs can attract males from miles away. A number of fascinating studies have focused on pheromone effects in mice. For example, when female mice are segregated from males, they stop having regular sex cycles. But when the female mice are exposed to the odor of the urine of a male mouse, all the cycles return in synchrony. If a pregnant female comes into contact with the odor pheromone produced by an unfamiliar male, she will abort and then become sexually receptive to the new mouse. After a mate has been found, courtship may arouse sexual motivation and synchronize the behavior of each animal so that actual mating, or copulation, can take place. Different species have evolved different behavior patterns in courtship. However, there are some common functions that courtship serves (Alcock, 1998). An animal must locate and identify a potential mate. Specific cues in the courtship pattern may differentiate closely related species, thus preventing crossbreeding and wasted energy on infertile matings. For example, different species of ducks make different head movements during courtship, and other species do not respond to these movements. Visual or auditory cues often enhance sexual arousal. In monkeys, there is a swelling and change in color in the genital area of the female during estrus. And just the sound of the male cooing may provide enough stimulation for female pigeons to ovulate. Tactile stimulation may also be important in sexual motivation, as evidenced by the fact that female cats are stimulated by the male to ovulate only during copulation. This is adaptive in that it allows the cat to retain her eggs until male sperm are available. In many animals, postural adjustments are required for copulation to take place. For example, in rodents such as the rat, the female must remain motionless and raise her hindquarters for the male to mount her successfully. The stereotyped courtship and mating activities among animals are other cues that sexual behavior is largely under biological control. |
To find out more about animal courtship and mating,
Connect to these sites:
Anorexia and Bulimia Association site
Aphrodisiac page
| Copyright ©2008 The McGraw-Hill Companies. All rights reserved. Any use is subject to the McGraw-Hill Higher Education is one of the many fine businesses of The McGraw-Hill Companies. Please visit our Technical support website at http://mhhe.com/support. |
 |