Seed set and seed ovule ratio for each indivdual capitula of Centaurea solstitialis Units: counts, percentage Missing data: no missing data Column headings: Treatment: control = spontaneous self-pollination, selfing = manual self-pollination, withinpop = crosses between two different individuals of the same population, betweenpop = crosses between two individuals from different populations within the same region, betweenregion = crosses between two individuals from two different randomly selected populations in two different world regions. Seed:Ovule_ratio = the percentage of ovules developing into seeds