Climate‐driven change in plant–insect interactions along elevation gradients

Abstract

Summary1. Global warming is predicted to dramatically alter communities' composition through differential colonization abilities, such as between sessile plants and their mobile herbivores. Novel interactions between previously non-overlapping species may, however, also be mediated by altered plants' responses to herbivore attack. 2. Syndromes of plant defences and tolerance are driven by inherited functional traits, biotic and abiotic conditions, and the geographical and historical contingencies affecting the community. Therefore, understanding climate change-driven herbivore responses and evolution towards a particular plant defence syndrome is key to forecasting species interactions in the near future. 3. In this paper, we first document variations in herbivory, and plant defences along altitudinal gradients that act as 'natural experiments'. We then use an empirical model to predict how specialist herbivore abundance may shift with respect to elevation in the near future. 4. Our field surveys and field experiment showed a decrease in herbivory with elevation. However, contrary to expectations, our meta-regression analyses showed that plant defences, particularly leaf toughness and flavonoid compounds, tend to be higher at high elevations, while secondary metabolites showed no clear trend with elevation. 5. Based on those results, we discuss how plant communities and species-specific plant defence syndromes will change in response to the climate-driven herbivore colonization of higher altitudes. Particularly, plant from high elevation, due to high protection against abiotic stress may be already ecologically fitted to resist the sudden increase in herbivory pressure that they will likely experience during global change.

Elevational gradients in plant defences and insect herbivory: recent advances in the field and prospects for future research

“…temperate versus tropical; Galmán et al 2018) may show variation in the functional form (linear versus non-linear, e.g. humpedshaped; Grytnes 2003, Rasmann et al 2014a, CallisDuehl et al 2017) and sign (positive versus negative) of the association between elevation and population or community-level variables (Rasmann et al 2014b) (Fig. 1E).…”

Spider foraging strategies dominate pest suppression in organic tea plantations

“…The major difference among these three tea plantations is altitude. Because insects are ectothermic, it is generally expected that insect herbivory rates decrease with elevation (Rasmann et al 2014). Farmers thus prefer to grow crops at higher elevations to limit negative effects of herbivores and pathogens (Poveda et al Fig.…”

High Rate of Protein Coding Sequence Evolution and Species Diversification in the Lycaenids

“…Although mechanisms promoting species diversification following the evolution of mutualism are still debated, several cases of diversification after the establishment of mutualistic interactions have been documented and concepts such as the ecological opportunity have emerged to explain them (Schluter, 2000;Ricklefs, 2010;Joy, 2013). The evolution of a mutualism between two partners may provide access to previously untapped environments or resources (Joy, 2013), or provides escape from antagonistic actors such as in ant-plant mutualism (Heil and McKey, 2003;Rasmann et al, 2014). Studying both the rate of molecular evolution and diversification in mutualistic lineages can shed light on the underlying processes.…”