Data from: Does co-history constrain information use? Evidence for generalized risk assessment in non-native prey

Though prey use a variety of information sources to assess predation risk, evolutionary co-history with a predator could constrain information use, and non-native prey might fail to recognize risk from a novel predator. Non-native prey might instead use generalized risk assessment, relying on general alarm signals from injured conspecifics rather than cues from predators. I tested the influence of shared predator-prey history on information use, comparing responses among three native and four non-native prey species to chemical cues from a native predator and cues from injured conspecific prey. Non-native prey demonstrated information generalism: (1) responding stronger to alarm cues released by injured conspecific prey than to cues from predators, and (2) responding similarly to alarm cues as to cues from predators consuming injured conspecific prey. By contrast, native prey multiple information sources were required to elicit the greatest defense. The influence of other sources of chemical information was not predicted by co-history with the predator: only one non-native snail responded to the predator; digestion was only important for two native species; the identity of injured prey was important for all prey; and predator and prey cues contributed additively to prey response. Information generalism, hypothesized to be costly in co-evolved interactions, could facilitate invasions as a driver of, or response to, introduction to novel habitats.