HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

(American Journal of Botany. 2009;96:507-518.) doi: 10.3732/ajb.0800216 © 2009 Botanical Society of America, Inc.

What's this?

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Martín-Bravo, S. Articles by Luceño, M. Search for Related Content PubMed Articles by Martín-Bravo, S. Articles by Luceño, M. Agricola Articles by Martín-Bravo, S. Articles by Luceño, M. Social Bookmarking                            What's this?

Is Oligomeris (Resedaceae) indigenous to North America? Molecular evidence for a natural colonization from the Old World¹

² Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide University, ctra. de Utrera km 1 41013 Sevilla, Spain ³ Botanic Garden of Madrid, CSIC, Pza. Murillo n° 2 28014 Madrid, Spain

ABSTRACT

Oligomeris linifolia constitutes one of the few examples of intercontinental disjunctions at the species level between the arid regions of the Old World and SW North America. The status of the American populations has been obscure, with some authors considering the populations to be introduced, whereas others believe them to be native. To clarify these conflicting opinions, we performed phylogeographic analyses using nuclear ribosomal ITS and plastid trnL-F and rps16 sequences to infer the origin of the disjunct American populations. Two independent molecular clock approaches based on ITS and cpDNA sequences (rbcL, matK, trnL-F) were used to estimate a divergence time of O. linifolia. Low levels of sequence divergence and estimates of relatively recent splits of Oligomeris lineages disagree with the vicariance hypotheses traditionally suggested to account for New–Old World disjunctions. In addition, significant genetic differentiation of American populations does not indicate a recent anthropogenic introduction. Morphological uniformity and the sharing of haplotypes between disjunct populations, together with the molecular clock results, suggest that a long-distance dispersal event from the Old Word to SW North America may have taken place during the Quaternary, in spite of limited dispersal mechanisms in Oligomeris.

Key Words: arid regions • biogeography • intercontinental disjunction • long-distance dispersal • molecular clock • Oligomeris • Resedaceae • vicariance

Received for publication 27 June 2008. Accepted for publication 2 October 2008.

FOOTNOTES

¹ The authors thank M. Míguez and F. J. Fernández for technical support; B. Guzmán and M. Escudero for helpful advice with molecular clock analyses; the curators of BM, CAS, EA, HBG, HUJ, LD, RNG, RSA, UC, UCR, UPOS, UPS, WAG, WU, and Z herbaria for the loan of specimens and granting permissions for DNA extractions; and S. C. Meyers, G. C. Tucker, and two anonymous reviewers for their critical reading and commenting of the manuscript. This research was supported by the Spanish Ministry of Science and Technology and the Andalusian Government through projects CGL2005-06017-C02-02/BOS and P06-RMM-4128, respectively.

⁴ Author for correspondence (e-mail: smarbra{at}upo.es); present address: Department of Molecular Biology and Biochemical Engineering, Pablo de Olavide University, ctra. de Utrera km 1, 41013, Sevilla, Spain; fax: + 34-954349813

CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				M. Escudero, V. Valcarcel, P. Vargas, and M. Luceno Significance of ecological vicariance and long-distance dispersal in the diversification of Carex sect. Spirostachyae (Cyperaceae) Am. J. Botany, November 1, 2009; 96(11): 2100 - 2114. [Abstract] [Full Text] [PDF]