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Title: Do major host shifts spark diversification in butterflies?
Abstract The Escape and Radiate Hypothesis posits that herbivorous insects and their host plants diversify through antagonistic coevolutionary adaptive radiation. For more than 50 years, it has inspired predictions about herbivorous insect macro‐evolution, but only recently have the resources begun to fall into place for rigorous testing of those predictions. Here, with comparative phylogenetic analyses of nymphalid butterflies, we test two of these predictions: that major host switches tend to increase species diversification and that such increases will be proportional to the scope of ecological opportunity afforded by a particular novel host association. We find that by and large the effect of major host‐use changes on butterfly diversity is the opposite of what was predicted; although it appears that the evolution of a few novel host associations can cause short‐term bursts of speciation, in general, major changes in host use tend to be linked to significant long‐term decreases in butterfly species richness.  more » « less
Award ID(s):
1744552
PAR ID:
10458726
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Ecology and Evolution
Volume:
10
Issue:
8
ISSN:
2045-7758
Format(s):
Medium: X Size: p. 3636-3646
Size(s):
p. 3636-3646
Sponsoring Org:
National Science Foundation
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