HOW ORGANISMS PARTITION HABITATS - DIFFERENT TYPES OF COMMUNITY ORGANIZATION CAN PRODUCE IDENTICAL PATTERNS

Patterns of habitat partitioning have been widely described, but how t he patterns are formed is as yet incompletely understood To document a nd describe the different types of community organization that can pro duce patterns of partitioning, I surveyed the literature to find examp les of habitat partitioning. I then identified, characterized, and tab ulated occurrences of the different types of community organization. I n ten years of Ecology, there were 66 instances of habitat partitionin g 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, respect ively), but there were also 8 examples of one-sided preferences, 4 exa mples of centrifugal organization, and 3 instances of niche contractio n. This indicates that a variety of community organizations can produc e patterns of partitioning and that shared preferences may occur more frequently in nature than generally thought. The presence of particula r types of organization was influenced by the kind of study organism, with shared preferences occurring more frequently than distinct prefer ences among autotrophs and among different-aged individuals of the sam e species. Distinct preferences occurred when species were partitioned on different hosts rather than along gradients, suggesting that the k inds of resources that species use in a habitat may also influence how patterns of partitioning are formed.