Systematics Section / ASPT
Bateman, Richard M , Tali, K , Fay, MF , Rudall, PJ , James, K .
Exploring the threshold of incipient sympatric speciation in European terrestrial orchids.
Phylogeny reconstruction of all European orchid species has identified morphological species pairs that show negligible sequence divergence and hence may represent recent speciation events. Supposedly phenologically isolated subspecies of Neotinea ustulata occur in near-sympatry across Europe. However, AFLP analyses demonstrate that genotype accurately reflects geographical location but that in each region there is little differentiation between early- and late-flowering populations, suggesting that this incipient (sub)speciation event has not (yet) succeeded. The equally widespread allogamous sister species Platanthera chlorantha and P. bifolia show only one nonspecies-specific variable site in ca 5 kb of sequences. Morphometric analysis reveals largely allometric differences except for two pollinator-determining characters of spur width and viscidial separation where chlorantha exceeds bifolia threefold. Rare natural hybrids suggest that these diagnostic characters are under simple Mendelian control, offering an opportunity to apply evo-devo techniques to a very recent and apparently sympatric speciation event.
1 - Estonian Agricultural University, Riia 181, Tartu, 51014, Estonia
2 - Royal Botanic Gardens, Kew, Jodrell Laboratory, Richmond, Surrey, TW9 3AB, UK
3 - Natural History Museum, Department of Botany, Cromwell Road, London, SW7 5BD, United Kingdom
Presentation Type: Paper
Location: Cottonwood A (Snowbird Center)
Date: Monday, August 2nd, 2004
Time: 10:45 AM