Open AccessField and experimental evidence that competition and ecological opportunity promote resource polymorphism
Author(s) -
MARTIN RYAN A.,
PFENNIG DAVID W.
Publication year - 2010
Publication title -
biological journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.906
H-Index - 112
eISSN - 1095-8312
pISSN - 0024-4066
DOI - 10.1111/j.1095-8312.2010.01380.x
Subject(s) - intraspecific competition , biology , ecology , diversification (marketing strategy) , competition (biology) , resource (disambiguation) , population , evolutionary biology , demography , marketing , sociology , business , computer network , computer science
Resource polymorphism – the occurrence within a single population of discrete intraspecific morphs showing differential resource use – has long been viewed as an important setting for evolutionary innovation and diversification. Yet, relatively few studies have evaluated the ecological factors that favour resource polymorphism. Here, we combine observations of natural populations with a controlled experiment to assess the role of intraspecific competition (specifically, the density of conspecifics) and ecological opportunity (specifically, the range of resources available) on the expression of resource polymorphism in spadefoot toad tadpoles. We found that greater conspecific densities and a greater range of available resources together promoted the expression of resource polymorphism. We conclude that, ecological opportunity, in the form of diverse available resources, along with intraspecific competition, may be a prerequisite for resource polymorphism to evolve, because such polymorphisms require diverse resources onto which each morph can specialize as an adaptive response to minimize competition. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society , 2010, 100 , 73–88.