MITOCHONDRIAL INTROGRESSION AND INCOMPLETE LINEAGE SORTING THROUGH SPACE AND TIME: PHYLOGENETICS OF CROTAPHYTID LIZARDS

doi:10.1111/j.1558-5646.2007.00239.x

If you are seeing this message, you may be experiencing temporary network problems. Please wait a few minutes and refresh the page. If the problem persists, you may wish to report it to your local Network Manager.

It is also possible that your web browser is not configured or not able to display style sheets. In this case, although the visual presentation will be degraded, the site should continue to be functional. We recommend using the latest version of Microsoft or Mozilla web browser to help minimise these problems.

Wiley InterScience

Evolution

Volume 61 Issue 12, Pages 2879 - 2897

Published Online: 29 Aug 2007

Published on behalf of the Society for the Study of Evolution

Go to Society Site

< Previous Abstract | Next Abstract >

Save Article to My Profile Download Citation Request Permissions

Abstract | References | Full Text: HTML, PDF (Size: 6875K) | Related Articles | Citation Tracking

MITOCHONDRIAL INTROGRESSION AND INCOMPLETE LINEAGE SORTING THROUGH SPACE AND TIME: PHYLOGENETICS OF CROTAPHYTID LIZARDS

Jimmy A. McGuire ^1,2 , Charles W. Linkem ³ , Michelle S. Koo ⁴ , Delbert W. Hutchison ⁵ , A. Kristopher Lappin ⁶ , David I. Orange ⁷ , Julio Lemos-Espinal ⁸ , Brett R. Riddle ⁹ , and Jef R. Jaeger ⁹

¹ Museum of Vertebrate Zoology and Department of Integrative Biology, 3101 Valley Life Sciences Building, University of California, Berkeley, California 94720-3160 ² E-mail: mcguirej@berkeley.edu ³ Department of Ecology and Evolutionary Biology and Natural History Museum & Biodiversity Research Center, University of Kansas, Dyche Hall, 1345 Jayhawk Blvd., Lawrence, Kansas 66045-7561 ⁴ Museum of Vertebrate Zoology, 3101 Valley Life Sciences Building, University of California, Berkeley, California 94720-3160 ⁵ Biology Department, Whitman College, 345 Boyer Avenue, Walla Walla, Washington DC 99362 ⁶ Biological Sciences Department, California State Polytechnic University, 3801 West Temple Avenue, Pomona, California 91768-2553 ⁷ CTB McGraw-Hill, 10548 Armstrong Boulevard, Mather, California 95655 ⁸ Laboratorio de Ecologia, UBIPRO, Facultad de Estudios Superiores, Iztacala UNAM, Av. de los Barrios No. 1, Los Reyes Iztacala, Tlalnepantla, edo. de Mexico, Mexico 54090 ⁹ School of Life Sciences, University of Nevada Las Vegas, 4505 Maryland Pkwy, Las Vegas, Nevada, 89154-4004

Associate Editor: K. Crandall

KEYWORDS

Bayesian phylogenetics • biogeography • crotaphytidae • ecological niche modeling • introgression conveyor

ABSTRACT

We investigate the roles of mitochondrial introgression and incomplete lineage sorting during the phylogenetic history of crotaphytid lizards. Our Bayesian phylogenetic estimate for Crotaphytidae is based on analysis of mitochondrial DNA sequence data for 408 individuals representing the 12 extant species of Crotaphytus and Gambelia. The mitochondrial phylogeny disagrees in several respects with a previously published morphological tree, as well as with conventional species designations, and we conclude that some of this disagreement stems from hybridization-mediated mitochondrial introgression, as well as from incomplete lineage sorting. Unidirectional introgression of Crotaphytus collaris (western collared lizard) mitochondria into C. reticulatus (reticulate collared lizard) populations in the Rio Grande Valley of Texas has resulted in the replacement of ancestral C. reticulatus mitochondria over approximately two-thirds of the total range of the species, a linear distance of ∼270 km. Introgression of C. collaris mitochondria into C. bicinctores (Great Basin collared lizard) populations in southwestern Arizona requires a more complex scenario because at least three temporally separated and superimposed introgression events appear to have occurred in this region. We propose an "introgression conveyor" model to explain this unique pattern of mitochondrial variation in this region. We show with ecological niche modeling that the predicted geographical ranges of C. collaris, C. bicinctores, and C. reticulatus during glacial maxima could have provided enhanced opportunities for past hybridization. Our analyses suggest that incomplete lineage sorting and/or introgression has further confounded the phylogenetic placements of additional species including C. nebrius, C. vestigium, C. insularis, C. grismeri, and perhaps G. copei. Despite many independent instances of interspecific hybridization among crotaphytid lizards, the species continue to maintain morphological and geographic cohesiveness throughout their ranges.