 |
Phylogeography of Letharia vulpina
Susanne Altermann Website last updated October 22, 2007 |
The yellow-green lichen growing on this stump (photo by Einar Timdal) is the morphologically defined lichenized fungus Letharia vulpina. Letharia vulpina (more pictures) likes to grow in open dry forest. It's geographic range includes vast parts of Western North America (map) and scattered regions of Europe and Africa (worldwide distribution map). It's not very specific about substrate but it's fond of Jeffrey pine, Sierra juniper, ponderosa pine, sugar pine, and old wood fence posts.
I'm using a DNA sequencing approach for both the fungi and their various algal partners to:
1) Establish a more complete geographic distribution of the the Letharia vulpina subspecies, Letharia vulpina 'vulpina' and Letharia vulpina 'lupina' (see Kroken and Taylor 2001 for details on the distinction between these two mostly-asexually reproducing lineages).
2) Determine which algal species are partnering with Letharia vulpina 'lupina' throughout its range (see Kroken and Taylor 2000).
3) Determine the extent of congruence in the phylogeographic structure of Letharia vulpina 'lupina' and its algal partners.
4) Determine whether high partnership specificity of Letharia vulpina 'vulpina' is maintained in the presence of Letharia vulpina 'lupina' and its algal partners. Based on Kroken and Taylor (2001), these lichenized fungi appear to have geographically disjunct distributions, with Letharia vulpina 'vulpina' in the coast ranges, and Letharia vulpina 'lupina' further inland.
5) Compare the phylogeographic structure of Letharia vulpina 'lupina' with that of plants and animals in the Pacific Northwest (see Soltis et al. 1997, Brunsfield et al. 2001). I am particularly interested in any genetic signature of post-Pleistocene dispersal into British Columbia.
Questions/Comments
If you have any questions or comments about this project, please don't hesitate to email or call me: 831-459-2832.
I am done collecting samples, and I am currently working on data analysis. Thank you to all my volunteer collectors!
Literature Cited on this site:
Arnerup, Jenny, Nils Hogberg, and Goran Thor. 2004. Phylogenetic analysis of multiple loci reveal the population structure within Letharia in the Caucasus and Morocco. Mycological Research 108 (Part 3):311-316.
Brunsfield, S.J., J. Sullivan, D.E. Soltis, and P.S. Soltis. 2001. Comparative phylogeography of North-Western North America: a synthesis. In Integrating Ecology and Evolution in a Spatial Context, edited by J. Silvertown and J. Antonovics: Blackwell Science.
Kroken, Scott, and W. Taylor John. 2000. Phylogenetic species, reproductive mode, and specificity of the green alga Trebouxia forming lichens with the fungal genus Letharia. Bryologist 103 (4):645-660.
Kroken, Scott, and W. Taylor John. 2001a. A gene genealogical approach to recognize phylogenetic species boundaries in the lichenized fungus Letharia. Mycologia 93 (1):38-53.
Soltis, Douglas E., Matthew A. Gitzendanner, Darren D. Strenge, and Pamela S. Soltis. 1997. Chloroplast DNA intraspecific phylogeography of plants from the Pacific Northwest of North America. Plant Systematics & Evolution 206 (1-4):353-373.
