All behavioral science is rooted in direct observation of humans and animals. The reactions of a whole organism are essential to understanding the interaction of various body systems and behavior. Some persons ask why tissue cultures are not used instead of animals. Tissue cultures never develop depression, alcoholism, autism or learning disorders, memory impairments, aggressive behavior, social abnormalities or problems that psychologists study, and that is why they are rarely useful to behavioral scientists. Natural Settings Others may ask why animals can't be studied in the wild rather than in the laboratory.
Psychologists do observe and study animals in natural environments.
But for many investigations, the laboratory is the only setting in which researchers can eliminate outside factors that alter results. The laboratory is also the only setting for investigating the risks humans are exposed to for example, the impacts of various types of air pollution on aspects of human health. There are many safeguards to assure that laboratory animals receive humane and ethical treatment. The U.S. Department of Agriculture is responsible for enforcement and periodic inspections of animal research facilities both public and private. The American Psychological Association has a Code of Ethics that includes prescriptions for the humane and ethical treatment of research animals.