Grouprearing_early instars_rawdata_Lindstedt et al.2017

Data from the defensive behaviour and potency of the chemical defende during the group rearing stage of the experiment

Ants Data from How to fight multiple enemies: target-specific chemical defences in an aposematic moth

Animals have evolved different defensive strategies to survive predation, among which chemical defences are particularly widespread and diverse. Here we investigate the function of chemical defence diversity, hypothesizing that such diversity has evolved as a response to multiple enemies. The aposematic wood tiger moth (<i>Arctia plantaginis</i>) displays conspicuous hindwing coloration and secretes distinct defensive fluids from their thoracic glands and abdomen. We presented the two defensive fluids from lab-reared moths to two biologically relevant predators, birds and ants, and measured their reaction in controlled bioassays (no information on colour was provided). We found that defensive fluids are target-specific: thoracic fluids, and particularly the 2-sec-butyl-3-methoxypyrazine (SBMP) which they contain, deterred birds, but caused no aversive response in ants. In contrast, abdominal fluids were particularly deterrent to ants, while birds did not find them repellent. Our study is the first to show evidence of a single species producing separate chemical defences targeted to different predator types, highlighting the importance of taking into account complex predator communities in studies on the evolution of prey defence diversity

Supplementary Methods and Results from How to fight multiple enemies: target-specific chemical defences in an aposematic moth

Supplementary methods and supplementary result

Electronic Supplementary Material from Ecological conditions alter cooperative behaviour and its costs in a chemically defended sawfly

The evolution of cooperation and social behaviour is often studied in isolation from the ecology of organisms. Yet, the selective environment under which individuals evolve is much more complex in nature, consisting of ecological and abiotic interactions in addition to social ones. Here, we measured the life-history costs of cooperative chemical defence in a gregarious social herbivore, <i>Diprion pini</i> pine sawfly larvae, and how these costs vary under different ecological conditions. We ran a rearing experiment where we manipulated diet (resin content) and attack intensity by repeatedly harassing larvae to produce a chemical defence. We show that forcing individuals to allocate more to cooperative defence (high attack intensity) incurred a clear cost by decreasing individual survival and potency of chemical defence. Cooperative behaviour and the magnitude of its costs were further shaped by host plant quality. The number of individuals participating in group defence, immune responses and female growth decreased on a high resin diet under high attack intensity. We also found some benefits of cheating: non-defending males had higher growth rates across treatments. Taking together, these results suggest that ecological interactions can shape the adaptive value of cooperative behaviour and maintain variation in the frequency of cooperation and cheating

bluetitsdata

Dataset from the bioassay in which blue tits responded to the defensive fluids of the wood tiger mot

Electronic Supplementary Material from Ecological conditions alter cooperative behaviour and its costs in a chemically defended sawfly

The evolution of cooperation and social behaviour is often studied in isolation from the ecology of organisms. Yet, the selective environment under which individuals evolve is much more complex in nature, consisting of ecological and abiotic interactions in addition to social ones. Here, we measured the life-history costs of cooperative chemical defence in a gregarious social herbivore, <i>Diprion pini</i> pine sawfly larvae, and how these costs vary under different ecological conditions. We ran a rearing experiment where we manipulated diet (resin content) and attack intensity by repeatedly harassing larvae to produce a chemical defence. We show that forcing individuals to allocate more to cooperative defence (high attack intensity) incurred a clear cost by decreasing individual survival and potency of chemical defence. Cooperative behaviour and the magnitude of its costs were further shaped by host plant quality. The number of individuals participating in group defence, immune responses and female growth decreased on a high resin diet under high attack intensity. We also found some benefits of cheating: non-defending males had higher growth rates across treatments. Taken together, these results suggest that ecological interactions can shape the adaptive value of cooperative behaviour and maintain variation in the frequency of cooperation and cheating