Journal - Proceedings of the Royal Society B: Biological Sciences

Abstract :

Competition has long been proposed as an important force instructuring mammalian communities. Although early work recognizedthat competition has a phylogenetic dimension, only with recentincreases in the availability of phylogenies have true phylogeneticinvestigations of mammalian community structure become possible.We test whether the phylogenetic structure of 142 assemblagesfrom three mammalian clades (New World monkeys, North Americanground squirrels and Australasian possums) shows the imprintof competition. The full set of assemblages display a highlysignificant tendency for members to be more distantly relatedthan expected by chance (phylogenetic overdispersion). The overdispersionis also significant within two of the clades (monkeys and squirrels)separately. This is the first demonstration of widespread overdispersionin mammal assemblages and implies an important role for eithercompetition between close relatives where traits are conserved,habitat filtering where distant relatives share convergent traits,or both.