1. The POLYADAPTATION (Adaptive mechanisms of ecological divergence in sibling allopolyploid lineages) project has investigated the genetics of sibling Dactylorhiza allopolyploids.

2. The differentiation of the taxa of the aggregate is ± sympatric, on the diploid level they are isolated by ecological divergence,A. hirsuta s. str. is isolated by allopolyploidy, and all species are facultative selffertilizers; thus hybridization is weak.