One of the biggest challenges in community ecology is explaining patterns of species diversity. We cannot hope to explain these patterns unless we understand mechanisms of species coexistence. Although there are numerous hypotheses about species coexistence, few have been demonstrated in nature with any degree of confidence.
Our theoretical developments have recently led to powerful new ways of testing species coexistence mechanisms. These tests use field manipulations to test directly for mechanism functioning. Unlike many other tests, which merely indicate consistency with mechanisms, these tests are definitive, and thus provide high confidence that the mechanism is working in the system. Most empirical studies in the lab are using these new methods.
The basis of these new methods is the quantification of mechanism strength and the functional components of mechanisms discussed next.