Abstract Detail



Biogeography

Willyard, Ann [1], Gernandt, David [2], Langer, Stephen K [3], Lopez Reyes, Alejandro [4], Potter, Kevin M [5].

Mitochondrial phylogeography of the ponderosa pines in the USA and Mexico.

The phylogeography of the ponderosa pines in the USA depends on their relationship to the California big-coned pines (Sabinianae) and to closely related taxa in Mexico and Central America. We used mitochondrial haplotypes based on repeated motifs in nad1 intron 2 for 18 Ponderosae taxa and four Sabinianae species (Pinaceae). The 27 haplotypes observed in 217 samples revealed that most mitochondrial haplotypes were not exclusive to a taxon, although some haplotypes were only found in one taxon. Shared haplotypes had a strong geographic pattern and a weaker taxonomic pattern. Each of 28 P. jeffreyi samples had a Ponderosae-style mitochondrial haplotype with most samples carrying a haplotype of a sympatric Ponderosae species. Two distinctive haplotypes (H4 and H7) were endemic to the Great Basin and are terminal nodes on the network. Our phylogenetic perspective based on wider taxonomic sampling suggests widespread unidirectional mitochondrial capture by P. jeffreyi. Haplotypes found in P. ponderosa sensu stricto, P. benthamiana, and the Sabinianae, which all grow west of the Great Basin, have more similarity to some haplotypes found in Mexican taxa than they have to the Ponderosae that grow in and to the east of the Great Basin (P. scopulorum and P. brachyptera). Unique haplotypes in the Great Basin suggest that at least one taxon arose in place and that these haplotypes have been maintained in isolation from other ponderosa pines. Altogether, our results indicate a history of complex and intriguing relationships among ponderosa pines across the western United States and Mexico.


1 - 36640 Yocum Loop, Sandy, OR, 97055, United States
2 - Universidad Nacional Autónoma De México, Apartado Postal 70-233, Mexico, 04510, Mexico
3 - 301 North Main St #214, Layton, UT, 84041
4 - Universidad Nacional Autonoma de Mexico, Departamento de Botanica, Ciudad de Mexico, CDMX, 04510, Mexico
5 - North Carolina State University, Department Of Forestry And Environmental Resources, 3041 Cornwallis Road, Research Triangle Park, NC, 27709, United States

Keywords:
biogeography
Jeffrey pine
Mexico
mitochondrial capture
Pinaceae
Pinus ponderosa
Ponderosae
Sabinianae
sympatry
western United States.

Presentation Type: Oral Paper
Number:
Abstract ID:216
Candidate for Awards:None


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