Host shifts and evolutionary radiations of butterflies

Abstract

Ehrlich and Raven proposed a model of coevolution where major host plant shifts of butterflies facilitate a burst of diversification driven by their arrival to a new adaptive zone. One prediction of this model is that reconstructions of historical diversification of butterflies should indicate an increase in diversification rate following major host shifts. Using reconstructed histories of 15 butterfly groups, I tested this prediction and found general agreement with Ehrlich and Raven's model. Butterfly lineages with an inferred major historical host shift showed evidence of diversification rate variation, with a significant acceleration following the host shift. Lineages without an inferred major host shift generally agreed with a constant-rate model of diversification. These results are consistent with the view that host plant associations have played a profound role in the evolutionary history of butterflies, and show that major shifts to chemically distinct plant groups leave a historical footprint that remains detectable today.

Specialization and generalization in the diversification of phytophagous insects: tests of the musical chairs and oscillation hypotheses

“…This definition of monophagy is somewhat broad and arbitrary, but it has been used extensively in the literature [6,32,33], including in a previous study that supported the oscillation hypothesis [5]. Nevertheless, it is important to keep in mind this family-based definition of monophagy when interpreting our results.…”

“…In particular, the assumption that host-plant associations are instrumental in shaping the diversity of insect herbivores has been supported by a number of empirical studies. For example, Janz et al [5] found a positive relationship between the species diversity of butterflies and the species diversity of their host-plant taxa, and Fordyce [6] reconstructed brief increases in butterfly diversification rates following major host shifts.…”

Dietary innovations spurred the diversification of ruminants during the Caenozoic

“…According to our results, mixed-feeding diets could have evolved as early as the Late Oligocene and have been widespread in ruminant lineages in the Early Miocene (around 24 Ma; [24,27,31]; figure 1a,c). We suggest that relying on both browse and grass probably permitted ruminants to radiate as a new type of highly seasonal, grass-patched ecosystems progressively spread around this time [32,52,53]. Furthermore, such diets may increase the 'threat tolerance' of isolated populations during habitat fragmentation in relation to such climatic shifts [47,54] and represent a favourable strategy during episodes of faunal turnovers, when changes in habitat and faunas may offer not only new ecological opportunities but also the appearance of unexpected competitors [12,47].…”

Egg laying site selection by a host plant specialist leaf miner moth at two intra-plant levels in the northern Chilean Atacama Desert

“…Revista Brasileira de Entomologia http://dx.doi.org/10.1590/S0085-56262014000300009 Egg laying site selection in phytophagous insects is a complex behavior, carried out by many adult insect females, whose importance has been largely acknowledged in the ecology and evolution of Lepidoptera (Thompson & Pellmyr 1991;Fordyce 2010;Celik 2013;D'Costa et al 2013;Forister et al 2013). It may be a critical step to provide an adequate place for the subsequent success of larval development (Rabasa et al 2005;De Sibio & Rossi 2012).…”