PREFACE 



From the beginnings of life, organisms have lived together in some 

 kind of grouping. Since the differentiation of plants and animals, 

 communities in which both occurred and interacted have undoubtedly 

 characterized the arrangement of living things on the face of the 

 earth. We know now that there are no habitats in which both 

 l)lant and animal organisms are able to live, in which both do not 

 occur and influence each other. In contrast, the development of the 

 science of ecology has been hindered in its organization and distorted 

 in its growth by the separate development of plant ecology on the 

 one hand and animal ecology on the other. 



The authors were brought together in this task of attempting to 

 correlate the fields of plant and animal ecology by the common belief 

 that it would tend to advance the science of ecology in general. It 

 was this common interest rather than agreement in all matters which 

 led to the initiation of this book as a joint project several years ago. 

 In part, it grew out of the fact that the junior author's experience in 

 dealing with the marine communities of the Puget Sound region had 

 led to the discovery of community phenomena paralleling those found 

 on land and fitting the system of classification in use by the senior 

 author. 



The phenomena under discussion naturally bring up the question 

 of the community processes, concepts, and nomenclature. A zoologist 

 may be unfamiliar with various ecological terms in use among plant 

 ecologists, and the reverse is also usually true. Here the writers have 

 not introduced all the terms which they are inclined to use in their 

 individual papers, designed for a more limited group of readers, but 

 have attempted to substitute less technical terms. Those terms ap- 

 plicable to communities are given to aggregations of organisms suffi- 

 ciently well known to enable the reader to build up a fairly clear 

 conception of the whole, so that the terms may be applied to the 

 proper grouping. For example, the term biome has been applied only 

 to those communities in which studies have established something of 

 the processes of development and the character of the final stage or 



