Ecotones, characterized by adjacent yet distinct biotic communities, provide natural laboratories in which to investigate how environmental selection influences the ecology and evolution of organisms. For wild herbivores, differential plant availability across sharp ecotones may be an important source of dietary‐based selection. We studied small herbivore diet composition across a sharp ecotone where two species of woodrat, Our results suggest that woodrats respond to fine‐scale environmental differences in plant availability that may require different metabolic strategies in order to balance nutrient acquisition while minimizing exposure to potentially toxic PSCs.
Little is known about the tolerances of mammalian herbivores to plant specialized metabolites across landscapes. We investigated the tolerances of two species of herbivorous woodrats, Toxin tolerance was analysed in the context of population structure across collection sites with microsatellite analyses. Genetic differentiation among woodrats collected from different locations was minimal within either species. Tolerance differed substantially between the two species, with The results imply that mammalian herbivores are adapted to the specialized metabolites of plants in their diet, and that this tolerance can extend several kilometres outside of the range of dietary items. That is, direct ecological exposure to the specialized chemistry of particular plant species is not a prerequisite for tolerance to these compounds. These findings lay the groundwork for additional studies to investigate the genetic mechanisms underlying toxin tolerance and to identify how these mechanisms are maintained across landscape‐level scales in mammalian herbivores.
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- Award ID(s):
- 1656497
- NSF-PAR ID:
- 10380740
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Functional Ecology
- Volume:
- 36
- Issue:
- 8
- ISSN:
- 0269-8463
- Page Range / eLocation ID:
- p. 2119-2131
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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