Ecology is the scientific study of the mutual relations between organisms and their environment.Ecological research on animals and plants focuses on their geographic distribution and the ways they adapt to a particular environment. It includes the study of seasonal cycles in plants and such animal behavior as eating habits, formation of groups, and the building of shelters of different kinds as a response to the particular climate, terrain, or materials found in the environment. Human ecology studies the way the physical characteristics of the environment affect social, economic, and political behavior. An example is the way individuals form a social structure that will enable them to adapt and survive in their particular environment: theclose-knit family of the Eskimo contrasts sharply with the looser social groupings of migratory workers or occupants of trailer camps. Similarly, the fact that a group of people live in a mountainous terrain or close to a river may determine their whole way of life.An increasing number of ecological studies have been made in the field of psychiatry and abnormal psychology. They include research on geographical distribution of mental disorders, urban- rural comparisons and the effects of special environments. A recent example is the Midtown Manhattan study of Srole and others (1962) which revealed that 9 per cent of the upper class, 18 per cent of the middle class and 28 per cent of the lower class living in the same area of New York City were afflicted with severe mental and emotional disturbances. (The incidence of individual disorders is reported in this book under each major reaction type.) A number of ecological studies have also been made in the field of social psychology. One area of research is the geographical distribution of voting patterns on different economic levels and in various parts of the country. Sectional loyalty such as the “solid South,” and minority group behavior such as “the Negro vote” are being re-examined today. Another example is the study of Wilner et al. (1952), who found that Negro and white families living in close proximity had more interaction and showed more respect for each other than others living widely apart—but this is by no means a universal finding. Moreover, mere physical distance cannot be easily separated from psychological circumstances such as the character of a housing development, its social climate, and the auspices under which it functions.Other studies have investigated the interactions between children in the same cabins at summer camps, people living in the same housing development (or even in the same court), and in the same resettlement project. Loomis and Beegle (1950) found that in such situations the mere geographical proximity has considerable effect on newly formed relationships, but as time goes on people become sorted out according to such psychological factors as interests, personality, nationality and social attitudes. In the resettlement communities, for example, ranchers tended to visit ranchers and farmers visited farmers. Barker and Wright coined the term “behavior setting” for such situations, and use the term “psychological ecology” for the influence of environment on attitudes, personality, and behavior. An example is the fact that we act differently in a doctor’s office, a classroom, and on a fishing trip. Note, however, that in these cases the environment is both physical and social.Ecological considerations are found in a wide variety of other investigations. The classic Western Electric study of factory workers engaged in wiring components indicated that the positions in the front of the room had higher status than positions in the rear; also, cliques were formed on the basis of proximity of workers and work of the same type (Roethlisberger and Dickson, 1939). Seating positions in a factory cafeteria have also been found to follow geographical lines: office workers, plant workers, and supervisory personnel usually sit in separate groups and form their friendships accordingly. Investigations of primitive tribes, such as the Jibaro Indians, show that their hostility toward other tribes is often in direct proportion to the distance from them (Danielsson, 1949). On the other hand, Steinzor (1949) found that in discussion groups, the “social distance” was greater for people next to each other than for people on opposite sides of the circle—in other words, people sitting opposite each other interacted more than people sitting next to each other.