Ecological and evolutionary distances from neighbouring plants do not influence leaf herbivory by chewing insects in a Neotropical savanna

Abstract

ABSTRACT Background Coexisting plant species frequently exhibit marked differences in leaf damage caused by chewing insects. Such variation in leaf herbivory has often been attributed to interspecific differences in leaf defensive traits, leaf nutritional quality and leaf abundance. Aims We aimed to investigate the hypothesis that plants surrounded by more similar neighbours tend to exhibit higher levels of herbivory than plants surrounded by less similar neighbours. Methods We sampled 27 tree and shrub species in 49 plots of 10 m2 located in a Neotropical savanna. For each of the 815 plants sampled, we quantified leaf damage, specific leaf area, leaf toughness, height, and conspecific abundance. We analysed the relationship between herbivory levels and plant traits comparing each individual with its neighbouring plants. The effect of phylogenetic similarity was addressed using the mean phylogenetic distance between a focal plant individual and its neighbours (i.e., the phylogenetic isolation). Results Leaf herbivory damage ranged from zero to 29.6%. We found that phylogenetic isolation, specific leaf area, plant height, and plant abundance were not related to differences in leaf herbivory at the individual level in a neighbourhood. Conclusions Our findings show that leaf herbivory damage of individual plants was not consistently influenced either by phylogenetic or by trait similarity with neighbours.