The team hypothesized that " the sexually dimorphic dorsal color patterns" would be most effective at deterring predators when paired with sex-specific behaviors.
So that with dimorphic species two unions, which may be called legitimate, are fully fertile; and two, which may be called illegitimate, are more or less infertile.
No one until lately would have imagined that in dimorphic and trimorphic plants the different lengths of the stamens and pistils, and their arrangement, could have been of any service, but now we know this to be the case.