Data from: Natural selection and the predictability of evolution in Timema stick insects

Predicting evolution remains difficult. We studied the evolution of
cryptic body coloration and pattern in a stick insect using 25 years of
field data, experiments, and genomics. We found that evolution is more
difficult to predict when it involves a balance between multiple selective
factors and uncertainty in environmental conditions than when it involves
feedback loops that cause consistent back-and-forth fluctuations.
Specifically, changes in color-morph frequencies are modestly predictable
through time (r2 = 0.14) and driven by complex selective regimes and
yearly fluctuations in climate. In contrast, temporal changes in
pattern-morph frequencies are highly predictable due to negative
frequency-dependent selection (r2 = 0.86). For both traits, however,
natural selection drives evolution around a dynamic equilibrium, providing
some predictability to the process.