How Organisms Partition Habitats: Different Types of Community Organization Can Produce Identical Patterns

Abstract

Patterns of habitat partitioning have been widely described, but how the patterns are formed is as yet incompletely understood. To document and describe the different types of community organization that can produce patterns of partitioning, I surveyed the literature to find examples of habitat partitioning. I then identified, characterized, and tabulated occurrences of the different types of community organization. In ten years of Ecology, there were 66 instances of habitat partitioning accompanied by experimental demonstrations of how the patterns were formed. Shared preferences and distinct preferences were most commonly cited as producing patterns of partitioning (34 and 17 times, respectively), but there were also 8 examples of one-sided preferences, 4 examples of centrifugal organization, and 3 instances of niche contraction. This indicates that a variety of community organizations can produce patterns of partitioning and that shared preferences may occur more frequently in nature than generally thought. The presence of particular types of organization was influenced by the kind of study organism, with shared preferences occurring more frequently than distinct preferences among autotrophs and among different-aged individuals of the same species. Distinct preferences occurred when species were partitioned on different hosts rather than along gradients, suggesting that the kinds of resources that species use in a habitat may also influence how patterns of partitioning are formed.