Get 20M+ Full-Text Papers For Less Than $1.50/day. Start a 7-Day Trial for You or Your Team.

Learn More →

HYBRID ORIGINS OF PLANT SPECIES

HYBRID ORIGINS OF PLANT SPECIES ▪ Abstract The origin of new homoploid species via hybridization is theoretically difficult because it requires the development of reproductive isolation in sympatry. Nonetheless, this mode is often and carelessly used by botanists to account for the formation of species that are morphologically intermediate with respect to related congeners. Here, I review experimental, theoretical, and empirical studies of homoploid hybrid speciation to evaluate the feasibility, tempo, and frequency of this mode. Theoretical models, simulation studies, and experimental syntheses of stabilized hybrid neospecies indicate that it is feasible, although evolutionary conditions are stringent. Hybrid speciation appears to be promoted by rapid chromosomal evolution and the availability of a suitable hybrid habitat. A selfing breeding system may enhance establishment of hybrid species, but this advantage appears to be counterbalanced by lower rates of natural hybridization among selfing taxa. Simulation studies and crossing experiments also suggest that hybrid speciation can be rapid—a prediction confirmed by the congruence observed between the genomes of early generation hybrids and ancient hybrid species. The frequency of this mode is less clear. Only eight natural examples in plants have been rigorously documented, suggesting that it may be rare. However, hybridization rates are highest in small or peripheral populations, and hybridization may be important as a stimulus for the genetic or chromosomal reorganization envisioned in founder effect and saltational models of speciation. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Annual Review of Ecology, Evolution, and Systematics Annual Reviews

HYBRID ORIGINS OF PLANT SPECIES

Download PDF
31 pages

Loading next page...
 
/lp/annual-reviews/hybrid-origins-of-plant-species-MdCC92H7xp

References

References for this paper are not available at this time. We will be adding them shortly, thank you for your patience.

Publisher
Annual Reviews
Copyright
Copyright © 1997 by Annual Reviews Inc. All rights reserved
Subject
Review Articles
ISSN
0066-4162
DOI
10.1146/annurev.ecolsys.28.1.359
Publisher site
See Article on Publisher Site

Abstract

▪ Abstract The origin of new homoploid species via hybridization is theoretically difficult because it requires the development of reproductive isolation in sympatry. Nonetheless, this mode is often and carelessly used by botanists to account for the formation of species that are morphologically intermediate with respect to related congeners. Here, I review experimental, theoretical, and empirical studies of homoploid hybrid speciation to evaluate the feasibility, tempo, and frequency of this mode. Theoretical models, simulation studies, and experimental syntheses of stabilized hybrid neospecies indicate that it is feasible, although evolutionary conditions are stringent. Hybrid speciation appears to be promoted by rapid chromosomal evolution and the availability of a suitable hybrid habitat. A selfing breeding system may enhance establishment of hybrid species, but this advantage appears to be counterbalanced by lower rates of natural hybridization among selfing taxa. Simulation studies and crossing experiments also suggest that hybrid speciation can be rapid—a prediction confirmed by the congruence observed between the genomes of early generation hybrids and ancient hybrid species. The frequency of this mode is less clear. Only eight natural examples in plants have been rigorously documented, suggesting that it may be rare. However, hybridization rates are highest in small or peripheral populations, and hybridization may be important as a stimulus for the genetic or chromosomal reorganization envisioned in founder effect and saltational models of speciation.

Journal

Annual Review of Ecology, Evolution, and Systematics – Annual Reviews

Published: Nov 1, 1997

There are no references for this article.