Owing to the remarkable development in mass communications, people everywhere are feeling new wants and are being exposed to new customs and ideas, while governments are forced to introduce still further innovations for the reasons given above.At the same time, the normal rate of social change throughout the world is taking place at a vastly accelerated speed compared with the past. For example, in the early industrialized countries ofEurope the process of industrialization — with all the far-reaching changes in social patterns that followed — was spread over nearly a century, whereas nowadays a developing nation may undergo the same process in a decade or so.All this has the effect of building up unusual pressures and tensions within the community and consequently presents serious problems for the government concerned,Additional social stresses may also occur because of the population explosion or problems arising from mass migration movements—themselves made relatively easy nowadays by modern means of transport.As a result of these factors, governments are becoming increasingly dependent on biologists and social scientists for planning the appropriate programs and putting them into effect.