Crosses were performed between 33 species representing seven recognized trends of divergence in Section Oncocyclus (Siem.) Baker of the genus Iris L. All tested combinations were cross-compatible, and the various F1 interspecific hybrids were fully fertile. We concluded that speciation in this group did not involve the buildup of internal reproductive isolation barriers. The various species of the highly specialized, insect-pollinated Oncocyclus irises are isolated from one another by geographic, ecological, and temporal mechanisms and by preferences of their pollinators.
No takes yet. Share an insight, caveat, or question.
Avishai et al. (1980) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: