Title

Molecular Phylogenetic Evidence Refuting the Hypothesis of Batoidea (Rays and Skates) as Derived Sharks

Authors

C. J. Douady, Dalhousie University - Halifax, Canada
Mine Dosay, Queen's University - Belfast, United Kingdom
Mahmood S. Shivji, Nova Southeastern UniversityFollow
Michael Stanhope, Queen's University - Belfast, United Kingdom

Document Type

Article

Publication Date

2-2003

Publication Title

Molecular Phylogenetics and Evolution

ISSN

1055-7903

Volume

26

Issue/No.

2

First Page

215

Last Page

221

Abstract

Early morphological studies regarding the evolutionary history of elasmobranchs suggested sharks and batoids (skates and rays) were respectively monophyletic. More modern morphological cladistic studies, however, have tended to suggest that batoids are derived sharks, closely related to sawsharks and angelsharks, a phylogenetic arrangement known as the Hypnosqualea hypothesis. Very few molecular studies addressing interordinal relationships of elasmobranchs have been published; the few that do exist, are very limited in terms of both taxon representation and/or aligned sequence positions, and are insufficient to answer the question of whether batoids are derived sharks. The purpose of this study was to address this issue with more complete taxon representation, concomitant with a reasonable number of aligned sequence positions. The data set included a 2.4-kb segment of the mitochondrial 12S rRNA—tRNA valine—16S rRNA locus, and in terms of taxa, representatives of two orders of Batoidea, at least one representative of all orders of sharks, and as an outgroup, the widely recognized sister group to elasmobranchs—Holocephali. The results provide the first convincing molecular evidence for shark monophyly and the rejection of the Hypnosqualea hypothesis. Our phylogenetic placement of batoids as a basal elasmobranch lineage means that much of the current thinking regarding the evolution of morphological and life history characteristics in elasmobranchs needs to be re-evaluated.

Comments

©2002 Elsevier Science (USA). All rights reserved.

NSUWorks Citation

Douady, C. J.; Mine Dosay; Mahmood S. Shivji; and Michael Stanhope. 2003. "Molecular Phylogenetic Evidence Refuting the Hypothesis of Batoidea (Rays and Skates) as Derived Sharks." Molecular Phylogenetics and Evolution 26, (2): 215-221. doi:10.1016/S1055-7903(02)00333-0.

ResearcherID

G-4080-2013

DOI

10.1016/S1055-7903(02)00333-0