Data from: Hot spots become cold spots: coevolution in variable temperature environments

Antagonistic coevolution between hosts and parasites is a key process in
the genesis and maintenance of biological diversity. Whereas
coevolutionary dynamics show distinct patterns under favourable
environmental conditions, the effects of more realistic, variable
conditions are largely unknown. We investigated the impact of a
fluctuating environment on antagonistic coevolution in experimental
microcosms of Pseudomonas fluorescens SBW25 and lytic phage SBWΦ2.
High-frequency temperature fluctuations caused no deviations from typical
coevolutionary arms-race dynamics. However, coevolution was stalled during
periods of high temperature under intermediate and low frequency
fluctuations, generating temporary coevolutionary coldspots. Temperature
variation affected population density, providing evidence that
eco-evolutionary feedbacks act through variable bacteria-phage encounter
rates. Our study shows that environmental fluctuations can drive
antagonistic species interactions into and out of coevolutionary cold and
hot spots. Whether coevolution persists or crashes depends on the
frequency of change and the environmental optima of both interacting
players.