Format

Send to:

Choose Destination
See comment in PubMed Commons below
Syst Biol. 2007 Apr;56(2):163-81.

Widespread genealogical nonmonophyly in species of Pinus subgenus Strobus.

Author information

  • 1Department of Biological and Physical Sciences, Montana State University-Billings, Billings, Montana 59101, USA. jsyring@msubillings.edu

Abstract

Phylogenetic relationships among Pinus species from subgenus Strobus remain unresolved despite combined efforts based on nrITS and cpDNA. To provide greater resolution among these taxa, a 900-bp intron from a late embryogenesis abundant (LEA)-like gene (IFG8612)was sequenced from 39 pine species, with two or more alleles representing 33 species. Nineteen of 33 species exhibited allelic nonmonphyly in the strict consensus tree, and 10 deviated significantly from allelic monophyly based on topology incongruence tests. Intraspecific nucleotide diversity ranged from 0.0 to 0.0211, and analysis of variance shows that nucleotide diversity was strongly associated (P < 0.0001)with the degree of species monophyly. Although species nonmonophyly complicates phylogenetic interpretations, this nuclear locus offers greater topological support than previously observed for cpDNA or nrITS. Lacking evidence for hybridization, recombination, or imperfect taxonomy, we feel that incomplete lineage sorting remains the best explanation for the polymorphisms shared among species. Depending on the species, coalescent expectations indicate that reciprocal monophyly will be more likely than paraphyly in 1.71 to 24.0 x 10(6) years, and that complete genome-wide coalescence in these species may require up to 76.3 x 10(6) years. The absence of allelic coalescence is a severe constraint in the application of phylogenetic methods in Pinus, and taxa sharing similar life history traits with Pinus are likely to show species nonmonophyly using nuclear markers.

PMID:
17454973
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Write to the Help Desk