Genetic endemism of Galapagos Pteridium

Hybridization experiments indicate that Pteridium aquilinum from Hawaii and P. aquilinum from the Galapagos Isles are intersterile. Both of these populations will cross readily with other New World collections of Pteridium. Evidence suggests that the Galapagos populations are genetically distinct from the South American populations. The genetic divergence of the Galapagos populations has not been accompanied by morphological divergence.