Imbalanced diversification of two Mediterranean sister genera (Bellis and Bellium, Asteraceae) within the same time frame
2011 (English)In: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 295, no 1-4, 109-118 p.Article in journal (Refereed) Published
The Daisies, Bellis and Bellium, form a monophyletic complex within the core Astereae (Asteraceae). Although most early diverging lineages show an African distribution, the core Astereae is today widespread on five continents with the Bellis/Bellium complex as the only representative in the Mediterranean basin. Molecular clock estimates placed the divergence of Astereae from its sister tribe Anthemideae in the Oligocene. Using a combination of three plastid genes, we estimated divergence times for different lineages of the tribe Astereae. This, together with temporal and biogeographical reconstructions using the nrITS region, allows placing and timing of the major lineages of the Bellis/Bellium complex. The age reconstruction places the divergence of the tribe Astereae in the late Miocene (18-19 million years ago), followed by an out-of-Africa dispersal into Asia where the worldwide expansion may have started. Our results suggest that the colonization of the Mediterranean basin by the Astereae started from Eurasia some 10 million years ago. A Messinian early divergence of the Bellis/Bellium complex in the Mediterranean was estimated. However, a parallel 4-million-year delay for the within-genera diversification was inferred, probably related to the establishment of the sclerophyllous Mediterranean forest. Despite a similar time frame for the within-genera diversification, today's species numbers differ considerably between Bellis (15 spp.) and Bellium (five spp.).
Place, publisher, year, edition, pages
2011. Vol. 295, no 1-4, 109-118 p.
Astereae, Bellis/Bellium complex, Diversification rates, Mediterranean climate, Sclerophyllous vegetation, West and Central Mediterranean basin
IdentifiersURN: urn:nbn:se:uu:diva-158325DOI: 10.1007/s00606-011-0468-5ISI: 000293026600008OAI: oai:DiVA.org:uu-158325DiVA: diva2:439007