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08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Phylogenetic relationships in Selaginellaceae based on RBCL sequences
1Department of Botany, Stockholm University, SE-106 91 Stockholm, Sweden, and Molecular Systematics Laboratory, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden;
American Journal of Botany
|June 14, 2011
Summary
This study establishes a phylogenetic framework for clubmosses (Selaginellaceae) using molecular data, revealing new groupings and evolutionary insights. It highlights recent diversification in tropical species and multiple independent evolutions of resurrection plants.
Area of Science:
- Botany
- Phylogenetics
- Molecular Biology
Background:
- The clubmoss family Selaginellaceae exhibits significant morphological, geographical, and ecological diversity.
- Understanding the evolutionary relationships within Selaginellaceae is crucial for its taxonomic and ecological studies.
Purpose of the Study:
- To develop a robust phylogenetic framework for the Selaginellaceae family.
- To investigate the monophyly of existing subgenera and identify new groupings based on molecular data.
Main Methods:
- Maximum parsimony analyses were conducted using molecular data.
- The chloroplast gene rbcL was sequenced for 62 species, representing approximately 10% of the family's diversity.
- Taxa selection encompassed morphological, geographical, and ecological diversity.
Main Results:
- Monophyly was supported for subgenera Selaginella and Tetragonostachys, while Stachygynandrum and Heterostachys were found to be polyphyletic.
- New groupings were identified, some with associated morphological (e.g., rhizophores) or ecological (e.g., xerophytism) synapomorphies.
- Despite a long fossil record, most living tropical species appear to be products of recent diversification events.
Conclusions:
- The study provides a refined phylogenetic framework for Selaginellaceae, challenging some traditional classifications.
- Evolutionary patterns suggest recent diversification in tropical lineages and multiple independent origins of resurrection plant adaptations.
- Further research is needed to elucidate the evolutionary history of many Selaginellaceae groups due to limited available data.
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