Biogeography lacks some spores. Spikemosses don't: Phylogeny, historical biogeography and phylogeography of Selaginella
2011 (English)Conference paper, Poster (Other academic)
Studying biogeography in a broad range of lineages is needed to pose general biogeographical hypotheses. However, plant biogeography studies have so far mainly focused on seed plants, and few have targeted plants that are dispersed by spores. In my PhD project I use the lycophyte family Selaginellaceae (spikemosses) as the study organism. The family has an origin in the Late Carboniferous, and it comprises the single genus Selaginella with approximately 700 species. The main species distribution is throughout subtropical and tropical areas, even though some ten percent of the species diversity is found in temperate regions. In contrast to most other spore dispersed plants, Selaginella is heterosporous meaning that two kinds of spores are produced, mega- and microspores. The spores give rise to a female and male gametophyte, respectively, implying that intragametophytic selfing is not possible. How does this affect the plants' ability to disperse?
The main focus of my studies lies on the occurrence of long-distance dispersal on different temporal, spatial, and phylogenetic scales in Selaginella. The first part of the project addresses the question if the disjunct distributions seen in Selaginella are due to long-distance dispersal or historical vicariance events. To start with, I will focus on historical biogeography in the family Selaginellaceae as a whole, and evaluate possible vicariance scenarios as a response to the breakup of Gondwana. Subsequently, studies on a more regional scale will be conducted by investigating biogeographical patterns in a well-supported group of taxa in Southeast Asia/Australasia. This is a region with extensive land mass changes due to, among other events, the collision between India and Asia in the Eocene, and sea level fluctuations. The second part of the project will be conducted at the intraspecific level. I will test if any phylogeographical patterns are discernable in Selaginella, and the main study object will be the single Swedish species, Selaginella selaginoides. Overall my PhD project aims to give us new insights into which impact long-distance dispersal has in shaping the biogeography of spore dispersed plants.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:uu:diva-166535OAI: oai:DiVA.org:uu-166535DiVA: diva2:476807
1st ForBio Annual Meeting, Bergen, Norway, 1-2 February, 2011