EVOLUTION IN PERIPHERAL ISOLATED POPULATIONS:<i>CARPODACUS</i>FINCHES ON THE CALIFORNIA ISLANDS

Power, Dennis M.

doi:10.1111/j.1558-5646.1979.tb04738.x

Cited by 9 publications

(5 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar discordance between patterns of similarity in covariance matrices and geographic or phylogenetic relationships among taxa was found in several other studies (Riska 1985;Lofsvold 1986;Kohn and Atchley 1988;Cheverud 1989;Wagner 1990;Steppan 1997). Such divergence in covariance patterns among populations is most consistent with diverse responses to local fluctuating selection pressures (Riska 1985;Arnold 1992), especially in peripheral populations that are subject to frequent variation in population density (Felsenstein 1976; see also Power 1979).…”

Section: Discussionsupporting

confidence: 81%

The Evolution of Sexual Dimorphism in the House Finch. I. Population Divergence in Morphological Covariance Structure

Badyaev

Hill

2000

Evol

View full text Add to dashboard Cite

Patterns of genetic variation and covariation strongly affect the rate and direction of evolutionary change by limiting the amount and form of genetic variation available to natural selection. We studied evolution of morphological variance-covariance structure among seven populations of house finches (Carpodacus mexicanus) with a known phylogenetic history. We examined the relationship between within-and among-population covariance structure and, in particular, tested the concordance between hierarchical changes in morphological variance-covariance structure and phylogenetic history of this species. We found that among-population morphological divergence in either males or females did not follow the within-population covariance patterns. Hierarchical patterns of similarity in morphological covariance matrices were not congruent with a priori defined historical pattern of population divergence. Both of these results point to the lack of proportionality in morphological covariance structure of finch populations, suggesting that random drift alone is unlikely to account for observed divergence. Furthermore, drift alone cannot explain the sex differences in within-and among-population covariance patterns or sex-specific patterns of evolution of covariance structure. Our results suggest that extensive among-population variation in sexual dimorphism in morphological covariance structure was produced by population differences in local selection pressures acting on each sex.

show abstract

Section: Discussionsupporting

confidence: 81%

The Evolution of Sexual Dimorphism in the House Finch. I. Population Divergence in Morphological Covariance Structure

Badyaev

Hill

2000

Evol

View full text Add to dashboard Cite

show abstract

“…It is well known that insular populations often differentiate rapidly. A recent study by Power (1979) has shown that greater divergence of house finch populations is found for California islands than for the adjacent mainland. However, this study also illustrates the difficulties of assessing the importance of isolation in archipelagic differentiation.…”

Section: Discussionmentioning

confidence: 98%

Riverine Barriers to Gene Flow and the Differentiation of Fence Lizard Populations

Pounds¹,

Jackson²

1981

Evolution

View full text Add to dashboard Cite

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Society for the Study of Evolution is collaborating with JSTOR to digitize, preserve and extend access to Evolution. Even prior to the advent of population genetics, it was held that the exchange of genes among populations retards differentiation and promotes the cohesiveness of species. Jordan (1905) maintained that the characters of a species remain "substantially uniform" if free movement of individuals is possible. This concept of a conservative evolutionary factor became a fundamental component of the synthetic theory of evolution (Dobzhansky, 1937; Mayr, 1942). Ehrlich and Raven (1969), questioning the validity of the traditional view, suggested that gene flow may play an inconsequential role in the cohesion of populations. Instead of stimulating research, this paper was the provenance of an influential viewpoint that relegates gene flow to a lower echelon of evolutionary factors. For example, Emmel (1976) wrote, "It therefore became apparent by the late 1960's that gene flow between populations seems to have little to do with holding species together as similar phenotypic units . . . . " We have contended that this neo-orthodoxy lacks an empirical base (Jackson and Pounds, 1979). The present empirical study focuses on the effect of gene flow on the divergence of neighboring demes. Theoretically, parapatric differentiation can occur (Jain and Bradshaw, 1966; Endler, 1973, 1977), and laboratory experiments have confirmed this (e.g., Endler, 1973, 1977). However, as laboratory and computer models often assume conditions not found in nature, examination of natural situations is imperative. Well-documented instances of natural parapatric 1 Present address: Department of Zoology, University of Florida, Gainesville, Florida 32611. LITERATURE CITED ANTONOVICS, J. 1971. The effects of a heterogeneous environment on the genetics of natural populations. Amer. Sci. 59:593-599. ATCHLEY, W. R., AND D. ANDERSON. 1978. Ratios and the statistical analysis of biological data.

show abstract

“…Although water barriers are known to limit song sparrow dispersal, other factors such as the dominant northwesterly pattern of wind in the region [ 9 ], biogeography [ 59 ] or habitat structure may alter dispersal and colonization patterns. For example, prior to 1950, song sparrows were rare or absent on Santa Cruz Island, potentially due to competitive exclusion by rufous–crowned sparrows ( Aimophila ruficeps [ 59 ]).…”

Section: Discussionmentioning

confidence: 99%

“…Early hypotheses on patterns of colonization and subsequent divergence of the Channel Island avifauna were based on morphological divergence and biogeography [ 8 ]. Species with strong morphological divergence and restricted distributions such as the island scrub jay were predicted to have colonized the Channel Islands in a single event, followed by limited post-colonization gene flow [ 8 , 9 ]. Mitochondrial data from the island scrub jay confirmed genetic isolation from the mainland species, the western scrub jay ( Aphelicoma californica ), for more than 150 Kya [ 10 ].…”

Section: Introductionmentioning

confidence: 99%

Genetic Divergence of an Avian Endemic on the Californian Channel Islands

et al. 2015

View full text Add to dashboard Cite

The Californian Channel Islands are near–shore islands with high levels of endemism, but extensive habitat loss has contributed to the decline or extinction of several endemic taxa. A key parameter for understanding patterns of endemism and demography in island populations is the magnitude of inter–island dispersal. This paper estimates the extent of migration and genetic differentiation in three extant and two extinct populations of Channel Island song sparrows (Melospiza melodia graminea). Inter–island differentiation was substantial (G''ST: 0.14–0.37), with San Miguel Island having the highest genetic divergence and lowest migration rates. Santa Rosa and Santa Cruz Island populations were less diverged with higher migration rates. Genetic signals of past population declines were detected in all of the extant populations. The Channel Island populations were significantly diverged from mainland populations of M. m. heermanni (G''ST: 0.30–0.64). Ten mtDNA haplotypes were recovered across the extant and extinct Channel Island population samples. Two of the ten haplotypes were shared between the Northern and Southern Channel Islands, with one of these haplotypes being detected on the Californian mainland. Our results suggest that there is little contemporary migration between islands, consistent with early explanations of avian biogeography in the Channel Islands, and that song sparrow populations on the northern Channel Islands are demographically independent.

show abstract

EVOLUTION IN PERIPHERAL ISOLATED POPULATIONS:CARPODACUSFINCHES ON THE CALIFORNIA ISLANDS

Cited by 9 publications

References 17 publications

The Evolution of Sexual Dimorphism in the House Finch. I. Population Divergence in Morphological Covariance Structure

The Evolution of Sexual Dimorphism in the House Finch. I. Population Divergence in Morphological Covariance Structure

Riverine Barriers to Gene Flow and the Differentiation of Fence Lizard Populations

Genetic Divergence of an Avian Endemic on the Californian Channel Islands

Contact Info

Product

Resources

About