BioOne.org will be down briefly for maintenance on 12 February 2025 between 18:00-21:00 Pacific Time US. We apologize for any inconvenience.
How to translate text using browser tools
1 October 2001 THE ROLE OF INTROGRESSIVE HYBRIDIZATION IN THE EVOLUTION OF THE GILA ROBUSTA COMPLEX (TELEOSTEI: CYPRINIDAE)
Anne S. Gerber, C. Alana Tibbets, Thomas E. Dowling
Author Affiliations +
Abstract

The extent and impact of introgressive hybridization was examined in the Gila robusta complex of cyprinid fishes using mitochondrial DNA (mtDNA) sequence variation. Lower Colorado River basin populations of G. robusta, G. elegans, and G. cypha exhibited distinct mtDNAs, with only limited introgression of G. elegans into G. cypha. The impact of hybridization was significant in upper Colorado River basin populations; most upper basin fishes sampled exhibited only G. cypha mtDNA haplotypes, with some individuals exhibiting mtDNA from G. elegans. The complete absence of G. robusta mtDNA, even in populations of morphologically pure G. robusta, indicates extensive introgression that predates human influence. Analysis of the geographic distribution of variation identified two distinctive G. elegans lineages; however, the small number of individuals and localities sampled precluded a comprehensive analysis. Analysis of haplotype and population networks for G. cypha mtDNAs from 15 localities revealed low divergence among haplotypes; however, significant frequency differences among populations within and among drainages were found, largely attributable to samples in the Little Colorado River region. This structure was not associated with G. cypha and G. robusta, as morphotypes from the same location are more similar than conspecific forms in other locations. This indicates that morphological and mtDNA variation are affected by different evolutionary forces in Colorado River Gila and illustrates how both hybridization and local adaptation can play important roles in evolution.

Corresponding Editor: J. Neigel

Anne S. Gerber, C. Alana Tibbets, and Thomas E. Dowling "THE ROLE OF INTROGRESSIVE HYBRIDIZATION IN THE EVOLUTION OF THE GILA ROBUSTA COMPLEX (TELEOSTEI: CYPRINIDAE)," Evolution 55(10), 2028-2039, (1 October 2001). https://doi.org/10.1554/0014-3820(2001)055[2028:TROIHI]2.0.CO;2
Received: 24 August 2000; Accepted: 1 June 2001; Published: 1 October 2001
JOURNAL ARTICLE
12 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

KEYWORDS
Cyprinidae
cytochrome b
gene diversity
Gila
introgressive hybridization
Nd2
single-stranded conformational polymorphism
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top