ABSTRACT
Ecology is the study of the causes of patterns of distribution and abundance of organisms. It is concerned with interactions between individuals and their physical and chemical environment, interactions between species and also interactions between individuals of the same species. The approach to ecology may be through field studies, laboratory experiments or mathematical modelling. Ideally ecological studies involve all three approaches because each provides new data or a new outlook which give rise to further questions or new ideas. During the 1970s the thrust of marine ecology moved away from the exploration of new habitats towards understanding more of the interrelations between organisms within the benthic community and with the overlying waters (Holme and McIntyre 1984), e.g. the ecosystem approach.
