Narrow hybrid zone between two subspecies of big sagebrush,Artemisia tridentata(Asteraceae). III. Developmental instability
- 1 September 1995
- journal article
- research article
- Published by Wiley in American Journal of Botany
- Vol. 82 (9) , 1144-1152
- https://doi.org/10.1002/j.1537-2197.1995.tb11586.x
Abstract
Stable hybrid zones are believed to occur because gene dispersal is opposed by selection, but the nature of this selection remains unclear. The dynamic equilibrium model postulates that hybridization disrupts coadapted gene complexes, leading to alterations in development and subsequent hybrid unfitness. Alternatively, the bounded hybrid superiority model assumes that selection is due to exogenous factors. Here, we examine the developmental instability of sagebrush across a narrow hybrid zone. The results show no difference among the parental and hybrid taxa for the majority of comparisons examined. When significant differences in developmental instability were observed, one of the parental taxa (mountain big sagebrush) was typically the least developmentally stable. Hybrids were found to be the least developmentally stable for only two of the 28 comparisons studied. Interestingly, for some comparisons, hybrids were themostdevelopmentallystable.These results contradict predictions of the dynamic equilibrium model. The sagebrush hybrid zone does not appear to be maintained by endogenous selection, as there is little indication that development is disrupted by hybridization.Keywords
Funding Information
- Wayne State University
This publication has 46 references indexed in Scilit:
- Fluctuating asymmetry in theMus musculushybrid zone: a heterotic effect in disrupted co-adapted genomesProceedings Of The Royal Society B-Biological Sciences, 1994
- Ecological Genetics of a Mosaic Hybrid Zone: Mitochondrial, Nuclear, and Reproductive Differentiation of Crickets by Soil TypeEvolution, 1989
- Hybrid zones-natural laboratories for evolutionary studiesTrends in Ecology & Evolution, 1988
- Homogamy in a hybrid zone in the alpine grasshopper Podisma pedestrisHeredity, 1987
- Population Dynamics and Regeneration of a Hybrid Zone Between Eucalyptus risdonii Hook-F and E amygdalina LabillAustralian Journal of Botany, 1986
- The genetic basis of hybrid inviability in the grasshopper Podisma pedestrisHeredity, 1981
- A Chromosomal Cline in the Grasshopper Podisma pedestrisEvolution, 1981
- Photosynthesis in black and red spruce and their hybrid derivatives: ecological isolation and hybrid adaptive inferiorityCanadian Journal of Botany, 1979
- Phenetics of Natural Populations. II. Asymmetry and Evolution in a LizardThe American Naturalist, 1967
- Speciation as a Stage in Evolutionary DivergenceThe American Naturalist, 1940