Taxonomy and putative hybridogenous speciation in Carex sect. Vesicariae and Phacocystis

In my PhD-project I will investigate the taxonomy and putative hybridogeneous speciation in two sections of Carex: namely sect. Vesicariae and sect. Phacocystis.

Hybridogeneous speciation in plants is usually coupled with a doubling of chromosomes in the hybrid offspring (allopolyploidy). Such speciation will lead to an immediate reproduction barrier between hybrid and parents, and is therefore a case of “instant speciation”. In Carex however, speciation seems to take place even though no apparent doubling of chromosomes in the hybrid is seen. In such events, it is thought that the speciation occurs through some kind of stabilization of a hybrid product by regaining fertility by restricted back-crossing of the primary hybrids with one or both putative parents.

In my PhD project, the aim is to study mechanisms and patterns for such putative hybridogeneous speciation. I also wish to clarify the taxonomy within the two Carex sections I am working with. By conducting both molecular analyses, morphological analyses, and analysis of pollen production and fertility in selected Carex taxa, I hope to get insight into how homoploid hybrids may form effective reproductive barriers against their parents as well as into how hybridogeneous taxa may become stabilized and eventually evolve into new species.

Published Aug. 18, 2015 1:09 PM - Last modified Mar. 3, 2016 3:49 PM