  Dynamic interspecific interactions are thought to contribute to fundamental
structures of ecological communities. Using the Yodzis framework of dominance
control versus founder control versus niche control, the importance of
intransitive loops in sub-communities in a source/sink or metacommunity
competition context is examined. It is found that a three-species sub-community
sampled from a species pool composed of nothing but dominance controlled
species pairs can result in a stable three species coexistence. It is shown
that if effect and response competition are balanced, the overall sub-community
will be persistent, anchored by one or more intransitive loops. It is proposed
that such an arrangement be referred to as an intransitive structure. It is
concluded that persistence of a sub-community (when species pairs in the
species pool are all dominance controlled) of more than three species is
possible only if it has an intransitive structure.
