The place of ecology in science and affairs

[First paragraphs...]
Basically, ecology is concerned with the distributions and densities of plants and animals; hence with the external factors of the environment which limit these distributions and densities; and with the internal factors in the organisation of communities and populations which regulate these distributions and densities. To put it shortly, ecology asks "How many organisms live where and why?" Man is himself concerned in these questions, indeed vitally concerned at the present day, as will be discussed later.
To learn what is the scope of ecology as a scientific discipline and how it may affect our attitude to human affairs, we should look briefly back on its development. This is not a lengthy task, for it took shape only during the early years of this century.