Data from: Breakdown of gametophytic self-incompatibility in subdivided populations

In many hermaphroditic flowering plants self-fertilization is prevented by
self-incompatibility (SI), often controlled by a single locus, the
S-locus. In single isolated populations, the maintenance of SI depends
chiefly on inbreeding depression and the number of SI alleles at the
S-locus. In subdivided populations, however, population subdivision has
complicated effects on both the number of SI alleles and the level of
inbreeding depression, rendering the maintenance of SI difficult to
predict. Here, we explore the conditions for the invasion of a
self-compatible mutant in a structured population. We find that the
maintenance of SI is strongly compromised when a population becomes
subdivided. We show that this effect is mainly caused by the decrease of
the local diversity of SI alleles rather than by a change in the dynamics
of inbreeding depression. Strikingly, we also find that the diversity of
SI alleles at the whole population level is a poor predictor of the
maintenance of SI. We discuss the implications of our results for the
interpretation of empirical data on the loss of SI in natural populations.