TY - JOUR
T1 - Using niche breadth theory to explain generalization in mutualisms
AU - Batstone, Rebecca T.
AU - Carscadden, Kelly A.
AU - Afkhami, Michelle E.
AU - Frederickson, Megan E.
N1 - Funding Information:
All authors conceived the ideas. R. T. Batstone and K. A. Carscadden contributed equally to the manuscript; both co-wrote and edited the manuscript, while K. A. Carscadden designed the figures. M. E. Afkhami and M. E., Frederickson provided guidance and substantial edits on each draft. For their insightful input on the manuscript, we thank G. Chomicki and an anonymous reviewer, as well as members of the Frederickson Lab (S. Meadley Dunphy, J. Laurich, K. Kaur, and M. Trychta), Emery Lab (N. Emery, R. La Rosa, A. Panetta, and C. Van Den Elzen), and M. Cadotte. We acknowledge the following funding sources: NSERC Discovery Grant (M. E., Frederickson), University of Miami (M. E. Afkhami), Ontario Graduate Scholarship (R. T. Batstone), the University of Toronto (M. E., Frederickson, R. T. Batstone), and the University of Colorado Boulder (K. A. Carscadden).
Publisher Copyright:
© 2018 by the Ecological Society of America
PY - 2018/5
Y1 - 2018/5
N2 - For a mutualism to remain evolutionarily stable, theory predicts that mutualists should limit their associations to high-quality partners. However, most mutualists either simultaneously or sequentially associate with multiple partners that confer the same type of reward. By viewing mutualisms through the lens of niche breadth evolution, we outline how the environment shapes partner availability and relative quality, and ultimately a focal mutualist's partner breadth. We argue that mutualists that associate with multiple partners may have a selective advantage compared to specialists for many reasons, including sampling, complementarity, and portfolio effects, as well as the possibility that broad partner breadth increases breadth along other niche axes. Furthermore, selection for narrow partner breadth is unlikely to be strong when the environment erodes variation in partner quality, reduces the costs of interacting with low-quality partners, spatially structures partner communities, or decreases the strength of mutualism. Thus, we should not be surprised that most mutualists have broad partner breadth, even if it allows for ineffective partners to persist.
AB - For a mutualism to remain evolutionarily stable, theory predicts that mutualists should limit their associations to high-quality partners. However, most mutualists either simultaneously or sequentially associate with multiple partners that confer the same type of reward. By viewing mutualisms through the lens of niche breadth evolution, we outline how the environment shapes partner availability and relative quality, and ultimately a focal mutualist's partner breadth. We argue that mutualists that associate with multiple partners may have a selective advantage compared to specialists for many reasons, including sampling, complementarity, and portfolio effects, as well as the possibility that broad partner breadth increases breadth along other niche axes. Furthermore, selection for narrow partner breadth is unlikely to be strong when the environment erodes variation in partner quality, reduces the costs of interacting with low-quality partners, spatially structures partner communities, or decreases the strength of mutualism. Thus, we should not be surprised that most mutualists have broad partner breadth, even if it allows for ineffective partners to persist.
KW - cheaters
KW - generalization
KW - mutualism
KW - niche breadth
KW - specialization
KW - symbiosis
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U2 - 10.1002/ecy.2188
DO - 10.1002/ecy.2188
M3 - Article
C2 - 29453827
AN - SCOPUS:85044319244
VL - 99
SP - 1039
EP - 1050
JO - Ecology
JF - Ecology
SN - 0012-9658
IS - 5
ER -