Data from: Does cohistory constrain information use? Evidence for generalized risk assessment in nonnative prey

Though prey use a variety of information sources to assess predation risk,
evolutionary cohistory with a predator could constrain information use,
and nonnative prey might fail to recognize risk from a novel predator.
Nonnative 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 nonnative
prey species to chemical cues from a native predator and cues from injured
conspecific prey. Nonnative 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,
for native prey, multiple information sources were required to elicit the
greatest defense. The influence of other sources of chemical information
was not predicted by cohistory with the predator: only one nonnative snail
responded to the predator; digestion was important for only 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 coevolved
interactions, could facilitate invasions as a driver of or response to
introduction to novel habitats.