Hybridisation between the British and the Spanish bluebell

The native British bluebell, Hyacinthoides non-scripta, is a spring flowering lily, which is well- known in natural, old forests across the British Isles. In the 17th century another bluebell taxon from the Iberian Peninsula was introduced as an ornamental plant. Since the beginning of the last century there have been reports of it in the wild, and it has recently been found to form fully fertile hybrids with the native bluebell. Both hybrids and the alien taxa are spreading, yet that usually occurs close to urban areas probably because of garden escapes. Several surveys and studies looking into the distribution of these taxa have suggested they may be putting the native British bluebell at risk, by outcompeting and replacing them in their natural habitats. However, our understanding of environmental drivers influencing alien invasion is confused by human impact, including on-going plantings and changing land use.
To better understand the dynamic between alien and native taxa, I study a natural hybrid zone between the British bluebell and its sister species, Hyacinthoides hispanica, in Spain, where there is minimal human influence. In this natural hybrid zone we learned from the hybrid’s flower morphologies and additional chloroplast data that the parents contribute symmetrically to the intermediate forms, and the hybrids appear without evident hybrid deficiencies. Gene flow is mainly mediated through pollen exchange, because clonal buds and seed dispersal are only important on an imminent range.
We will use genome-wide markers to get an understanding of patterns of introgression across hundreds of loci.