Patterns of Genetic Differentiation in Salamanders of the Desmognathus ochrophaeus Complex (Amphibia: Plethodontidae)

Tilley, Stephen G.; Mahoney, Meredith J.

doi:10.2307/1466979

Cited by 110 publications

(120 citation statements)

References 87 publications

Supporting

Mentioning

114

Contrasting

Unclassified

Order By: Relevance

“…In related taxa in eastern North America, many nearly cryptic species have been recognized (19,22,31). I suggest that there are historical reasons for the differences in pattern in eastern and western North America.…”

Section: Discussionmentioning

confidence: 99%

Incipient species formation in salamanders of the Ensatina complex

Wake

1997

Proc. Natl. Acad. Sci. U.S.A.

156

150

View full text Add to dashboard Cite

The Ensatina eschscholtzii complex of plethodontid salamanders, a well-known ''ring species,'' is thought to illustrate stages in the speciation process. Early research, based on morphology and coloration, has been extended by the incorporation of studies of protein variation and mitochondrial DNA sequences. The new data show that the complex includes a number of geographically and genetically distinct components that are at or near the species level. The complex is old and apparently has undergone instances of range contraction, isolation, differentiation, and then expansion and secondary contact. While the hypothesis that speciation is retarded by gene f low around the ring is not supported by molecular data, the general biogeographical hypothesis is supported. There is evidence of a north to south range expansion along two axes, with secondary contact and completion of the ring in southern California. Current research targets regions once thought to show primary intergradation, but which molecular markers reveal to be zones of secondary contact. Here emphasis is on the subspecies E. e. xanthoptica, which is involved in four distinct secondary contacts in central California. There is evidence of renewed genetic interactions upon recontact, with greater genetic differentiation within xanthoptica than between it and some of the interacting populations. The complex presents a full array of intermediate conditions between well-marked species and geographically variable populations. Geographically differentiated segments represent a diversity of depths of time of isolation and admixture, ref lecting the complicated geomorphological history of California. Ensatina illustrates the continuing difficulty in making taxonomic assignments in complexes studied during species formation.

show abstract

Section: Discussionmentioning

confidence: 99%

Incipient species formation in salamanders of the Ensatina complex

Wake

1997

Proc. Natl. Acad. Sci. U.S.A.

156

150

View full text Add to dashboard Cite

show abstract

“…In their reanalysis, Coyne and Orr (1997) also found a higher rate of evolution of hybrid sterility than hybrid inviability. As Coyne and Orr (1997) pointed out, the data from Drosophila are unique with respect to their quantity and degree of detail and are likely to remain so, due to the great number of species that can hybridize and the ease of measuring preand postzygotic isolation in the laboratory.In plethodontid salamanders of the Desmognathus ochrophaeus complex, Tilley et al (1990) and Tilley and Mahoney (1996) found that level of behavioral (prezygotic) isolation among populations cannot be predicted simply from genetic distances. Few other studies of which we are aware involved simultaneous investigation of both reproductive isolation and genetic divergence in amphibians.…”

mentioning

confidence: 99%

“…In plethodontid salamanders of the Desmognathus ochrophaeus complex, Tilley et al (1990) and Tilley and Mahoney (1996) found that level of behavioral (prezygotic) isolation among populations cannot be predicted simply from genetic distances. Few other studies of which we are aware involved simultaneous investigation of both reproductive isolation and genetic divergence in amphibians.…”

mentioning

confidence: 99%

Patterns of Postzygotic Isolation in Frogs

1998

View full text Add to dashboard Cite

Abstract.-From literature data on 116 taxa crosses involving 46 species of frogs, we found a positive correlation between degree of divergence (measured as Nei's genetic distance, D) and degree of postzygotic isolation. In anurans, hybrid sterility appears to evolve more quickly than inviability, which is consistent with the conclusions of other studies that involved Drosophila species. The lower threshold of D = 0.30 for evolution of hybrid inviability that we found is similar to that observed for Drosophila. This consistency suggests that there may be a general pattern in the acquisition of reproductive isolation in animals.Key words.-Anura, comparative method, frogs, reproductive isolation, speciation.Received February 3, 1998. Accepted August 10, 1998 A variety of approaches have been presented to elucidate the relationship between reproductive isolation (the defining feature of the speciation process according to adherents of the biological species concept) and degree of genetic divergence (e.g., Ayala et al. 1974). Coyne and Orr (1989,1997) have presented the most comprehensive surveys in this area, using data from hybridization between species of Drosophila. They found that strength of both prezygotic and postzygotic isolation barriers are positively correlated with pairwise genetic distance (and thus, presumably, time of divergence) between species. Although Coyne and Orr (1989) could not detect a significant difference between rates of acquisition of hybrid sterility and hybrid inviability, their original test was criticized for lack of statistical power (Wu 1992). Wu and Davis (1993) presented various lines of evidence that strongly suggest that the rate of evolution of hybrid sterility must be much greater than that of hybrid inviability in Drosophila. In their reanalysis, Coyne and Orr (1997) also found a higher rate of evolution of hybrid sterility than hybrid inviability. As Coyne and Orr (1997) pointed out, the data from Drosophila are unique with respect to their quantity and degree of detail and are likely to remain so, due to the great number of species that can hybridize and the ease of measuring preand postzygotic isolation in the laboratory.In plethodontid salamanders of the Desmognathus ochrophaeus complex, Tilley et al. (1990) and Tilley and Mahoney (1996) found that level of behavioral (prezygotic) isolation among populations cannot be predicted simply from genetic distances. Few other studies of which we are aware involved simultaneous investigation of both reproductive isolation and genetic divergence in amphibians. Anurans (frogs) in particular have the potential to yield many insights into the evolution of reproductive isolation because the reproductive biology of some taxa has been studied intensively (reviewed by Duellman and Trueb 1994). In particular, premating isolation mechanisms between closely related species are already documented for several groups (e.g., W. E Blair 1956Blair , 1958aBlair ,b, 1964Blair , 1972Gerhardt 1974;Ryan 1985;Ryan and Rand 1995), and the degree o...

show abstract

“…A single male and single female were paired for a standard period, and mating (insemination) was scored as present or absent. We used data on nine populations, now grouped as three species: D. carolinensis, D. ocoee, and D. orestes (35).…”

Section: Methodsmentioning

confidence: 99%

Dimensionality of mate choice, sexual isolation, and speciation

Hohenlohe

Arnold

2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Multiple cues, across multiple sensory modalities, are involved in mate choice in a wide range of animal taxa. This multiplicity leads to the prediction that, in adaptive radiations, sexual isolation results from divergence in multiple dimensions. However, difficulties in directly measuring preferences and detecting multiple effects limit our ability to empirically assess the number of independent traits contributing to mate choice and sexual isolation. We present an approach to estimate the dimensionality of sexual isolation using mating trials across groups of related populations. We analyze nine radiations: seven in fruit flies (Drosophila) and one each in salamanders (Desmognathus) and cichlid fishes (Pseudotropheus). We find strong evidence that multiple latent traits-linear combinations of phenotypic traits and preferences-are responsible for the patterns of sexual isolation in all nine radiations but that dimensionality has a strong upper limit. Just two latent traits are implicated in the majority of cases. Mapping along latent trait axes tests predictions of sexual-selection models and allows correlation with specific phenotypic traits and functional components of mate choice. We find support for the role of stabilizing natural selection on the sexually selected (male) traits. In the cichlids, latent-trait axes incorporate male-coloration patterns and exhibit convergence as well as divergence among populations. In the salamanders, temporal patterning in sensory modalities and male vs. female preferences are reflected in different latent-trait axes.behavioral isolation | female preference | multidimensional scaling | prezygotic isolation | sexual selection

show abstract

Patterns of Genetic Differentiation in Salamanders of the Desmognathus ochrophaeus Complex (Amphibia: Plethodontidae)

Cited by 110 publications

References 87 publications

Incipient species formation in salamanders of the Ensatina complex

Incipient species formation in salamanders of the Ensatina complex

Patterns of Postzygotic Isolation in Frogs

Dimensionality of mate choice, sexual isolation, and speciation

Contact Info

Product

Resources

About