Pattern and chance in the structure of model and natural communities.

Abstract

Reanalysis of data on the Galapagos finch fauna reveals a significant trend of bill size assortment in both the ground finches (Geospiza) and tree finches (Camarhynchus), ie size-dissimilar species sets are more common than expected. There was no evidence for size adjustment in either group, although available sample sizes (islands with complete size data) are so small that this lack of pattern is inconclusive. -from Authors