Abstract Detail

Systematics Section/ASPT

Moore, Abigail [1], Kadereit, Joachim [2].

In situ or ex situ origin of Alpine diversity: the evolution of soil preference in Minuartia series Laricifoliae (Caryophyllaceae).

Soil specialization is often considered an important factor in evolutionary diversification. A classic example of divergence related to different soil types is the dichotomy between calcicole and calcifuge plants growing on calcareous and siliceous soils. This dichotomy is especially prominent in the European Alps, where many genera contain pairs of closely related species, one calcicole and one calcifuge. These species are generally hypothesized to have diverged in the Alps, perhaps as a result of range shifts in response to glacial-interglacial cycles. However, many of these species also have relatives outside the Alps and it is possible that the soil diversity in the Alps simply allows the coexistence of related species whose edaphic differentiation took place deeper in the phylogeny and in some other part of their range. We examined the origin of edaphic differentiation in a pair of taxa that grow in the Alps: the calcicole Minuartia laricifolia subsp. kitaibelii and the calcifuge M. laricifolia subsp. laricifolia. The two taxa are morphologically similar but have non-overlapping distributions. They are members of Minuartia series Laricifoliae, which consists of 11 taxa from the European mountains, especially the Alps and various mountain ranges in the Balkan Peninsula. All members of series Laricifoliae grow in open, rocky habitats, and all but one generalist are confined to particular substrates, with three taxa endemic to serpentine, six taxa endemic to calcareous substrates, and one endemic to siliceous rock. We used internal transcribed spacer and external transcribed spacer sequence data to examine the relationships, substrate evolution and biogeographical history within series Laricifoliae. Minuartia laricifolia subspp. kitaibelii (calcicole) and laricifolia (calcifuge) are not each other’s closest relatives. Instead, each taxon is more closely related to Balkan species and therefore must have reached the Alps independently. Series Laricifoliae as a whole is ancestrally calcicole and M. laricifolia subsp. kitaibelii inherited this ancestral calcicole ecology. In contrast, subsp. laricifolia is a member of a clade that also contains two of the three serpentine endemics and the only generalist (which also mainly grows on serpentine). These results imply that the Alps were not the site of edaphic differentiation, but that, instead, species that were already differentiated in terms of soil preference were able to take advantage of the Alpine substrate diversity.

Broader Impacts:

1 - Johannes Gutenberg Universität Mainz, Institut Für Spezielle Botanik, Anselm Franz Von Bentzel Weg 9a, Mainz, GERMANY, D-55128, USA
2 - MAINZ UNIVERSITY, INSTITUT FUR SPEZIELLE BOTANIK, Mainz, N/A, D-55099, Germany

Keywords:
edaphic endemism
Phylogenetics
calcicole
calcifuge
Balkan Peninsula.

Presentation Type: Oral Paper:Papers for Sections
Session: 13
Location: Rosedown/Riverside Hilton
Date: Monday, July 29th, 2013
Time: 4:30 PM
Number: 13012
Abstract ID:529
Candidate for Awards:George R. Cooley Award