Climate‐driven diversity dynamics in plants and plant‐feeding insects

Abstract

The origin of species-rich insect-plant food webs has traditionally been explained by diversifying antagonistic coevolution between plant defences and herbivore counter-defences. However, recent studies combining paleoclimatic reconstructions with time-calibrated phylogenies suggest that variation in global climate determines the distribution, abundance and diversity of plant clades and, hence, indirectly influences the balance between speciation and extinction in associated herbivore groups. Extant insect communities tend to be richest on common plant species that have many close relatives. This could be explained either by climatedriven diffuse cospeciation between plants and insects, or by elevated speciation and reduced extinction in herbivore lineages associated with expanding host taxa (resources). Progress in paleovegetation reconstructions in combination with the rapidly increasing availability of fossil-calibrated phylogenies provide means to discern between these alternative hypotheses. In particular, the ÔDiffuse cospeciationÕ scenario predicts closely matching main diversification periods in plants and in the insects that feed upon them, while the ÔResource abundance-dependent diversificationÕ hypothesis predicts that both positive and negative responses of insect diversity are lagged in relation to host-plant availability. The dramatic Cenozoic changes in global climate provide multiple possibilities for studying the mechanisms by which climatic shifts may drive diversity dynamics in plants and insect herbivores.

Life history traits, but not phylogeny, drive compositional patterns in a butterfly metacommunity

“…The diversification period of the main lineages of butterflies, including those in our study, coincides with the first radiation of Angiosperm (125-90 Mya;Crane et al 1995, Wahlberg et al 2013. Climatic shifts after the K-Pg boundary might have influenced plant distribution and net diversification rates in different biomes across the globe, and this might have led to diversification of plant-feeding insects such as butterflies (Nyman et al 2012). Most butterfly subfamily lineages might also have diversified after the K-Pg boundary (see also Fig.…”

“…Most butterfly subfamily lineages might also have diversified after the K-Pg boundary (see also Fig. Analyzing similar large-scale phylogenetic conservatism in butterflies might thus provide insights on the amount and origin of codiversification and coevolution among butterflies and plants (Nyman et al 2012). Climatic shifts after the K-Pg boundary might have influenced plant distribution and net diversification rates in different biomes across the globe, and this might have led to diversification of plant-feeding insects such as butterflies (Nyman et al 2012).…”

Delayed colonisation of Acacia by thrips and the timing of host-conservatism and behavioural specialisation

“…Shifting to a new host plant can result from trade-offs between alternative environments associated with natural enemies [56,57] and larval or oviposition performance on alternative hosts [58-61]. Thrips colonised Acacia at a time when it presumably supported a similar diversity of insects as it does today [62].…”

Multispecies interactions across trophic levels at macroscales: retrospective and future directions

“…Historical effects such as those related to paleoclimatic changes can strongly influence present‐day diversity patterns in both tropical and extra‐tropical regions (Sandel et al , Blach‐Overgaard et al ). However, to what extent they influence cross‐trophic biotic interactions among multiple species at large spatial and temporal scales remains unclear (Nyman et al , Blois et al ). For instance, the phylogenetic structure of palm species assemblages worldwide differs among major biogeographic regions and this can be attributed to climate change and shifts of tropical rainforests during the Cenozoic (Kissling et al ).…”