A community has already been defined as the sum 

 total of the populations in a given area. One may 

 think of a forest or other habitat with its many 

 kinds of plants and animals as a community. Another 

 way of thinking of this ecological unit is in terms of 

 functions; by definition, the community must include 

 all the functions of its many populations. This means 

 that everything said about populations must apply to 

 communities; however, as one might expect by now, a 

 community is more complex than the sum of its parts. 



THE NATURE OF THE COMMUNITY 



Communities are so complex that their true nature 

 probably is unappreciated. However, two concepts, 

 superorganism and continuum, give some idea of 

 their nature. 



THE COMMUNITY, A SUPERORGANISM? 



The community as a whole may be treated as an 

 entity, a superorganism similar to a living organism or 

 to many organisms, especially in terms of its func- 

 tions. The similar functions include fluctuations, 

 equilibrium, influence on environment, relations with 

 others of its kind, life cycles, division of labor, or- 

 ganization, adaptations, regulation, and definite 



structure. In varying degrees these functions are the 

 subject of this chapter. Some consideration of them 

 now serves to illustrate the concept of a community 

 as a superorganism. 



Life cycles in the form of succession show that com- 

 munities originate ("birth"), grow, mature, and die. 

 Only stable, climax communities have a means of 

 self-production and perpetuation, but a function 

 analogous to reproduction exists where competition 

 causes one community to replace another (succes- 

 sion). Also, division of labor is found in plants pro- 

 viding food through photosynthesis, in plants im- 

 proving habitat conditions, and in all organisms 

 having different functions, discrete, but working to- 

 gether in a dynamic equilibrium. Such segregated 

 functions often are needed by, and thus benefit, the 

 various specialized creatures. In addition, organisms 

 providing necessary functions automatically assume 

 a position of some permanence in the community. 

 Since complex organization is the rule in communi- 

 ties, individual plants and animals must conform or 

 be adapted to life within their locale. Adaptations in 

 each population are such that the activities of species 

 are integrated so that a local area's life is regulated 

 by its internal units. This dynamic process of pre- 

 venting extreme conditions resulting from overactivity 

 of any species causes a trend toward community 

 equilibrium. Finally, definite community structure 



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