Present address: Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St., New Haven, CT 06520, USA.
Morphological diversity and ecological similarity: versatility of muscular and skeletal morphologies enables ecological convergence in shrews
Article first published online: 23 NOV 2009
© 2009 The Authors. Journal compilation © 2009 British Ecological Society
Volume 24, Issue 3, pages 556–565, June 2010
How to Cite
Young, R. L., Sweeney, M. J. and Badyaev, A. V. (2010), Morphological diversity and ecological similarity: versatility of muscular and skeletal morphologies enables ecological convergence in shrews. Functional Ecology, 24: 556–565. doi: 10.1111/j.1365-2435.2009.01664.x
- Issue published online: 8 APR 2010
- Article first published online: 23 NOV 2009
- Received 23 March 2009; accepted 20 October 2009 Handling Editor: Peter Wainwright
- ecological convergence;
- morphological versatility;
1. Ecological convergence in morphology among taxa of distinct evolutionary histories is a common illustration of the efficacy of natural selection. Ecological convergence is often enabled by functional redundancy of complex morphological structures, such that modification of existing morphologies in response to similar functional requirements can lead to the development and evolution of morphological diversity. Thus, studies of the mechanisms that enable the development of similar adaptations in taxa with distinct morphologies provide important insights into both the evolution of past adaptations and patterns of future evolutionary divergence.
2. Here, we examine mechanisms that have enabled ecological convergence in foraging morphology among four geographically isolated and morphologically distinct populations of shrews: south-eastern Arizona and north-central New Mexico populations of the montane shrews (Sorex monticolus) and northern California and north-central Montana populations of the vagrant shrew (S. vagrans).
3. We show that despite overlap in diet, populations had distinct skeletal and muscular morphologies of the mandible. This association between ecological convergence and morphological uniqueness among populations was enabled by versatility of foraging morphologies that generated similar functional outputs.
4. In addition, we found that populations exhibited unique skeletal and muscular correlations with diet suggesting that distinct muscular and morphological components of the complex foraging apparatus can be used for a particular resource. This result corroborates a previous finding that extensive modularity in mandibular development allows diverse morphologies to generate equivalent functions and utilize similar resources across taxa.
5. Synthesis. We conclude that the observed functional and ecological convergences resulted from population-specific musculoskeletal interactions, and suggest that the differences in skeletal and muscular morphologies observed among these populations reflect evolved differences in plasticity of the skeletal and muscular components of the mandible.