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Age, phylogeography and population structure of the microendemic banded spring snail, Mexipyrgus churinceanus
TLDR
There is strong evidence of long‐term isolation of three regions, suggesting that these regions represent evolutionarily distinct lineages, and Southeastern populations show evidence of range expansion and a strong influence of genetic drift. Expand
Next generation phylogeography of cave and surface Astyanax mexicanus.
TLDR
A high-resolution phylogeography is reconstructed for Astyanax mexicanus cave populations from the Sabinos and Río Subterráneo caves and it is shown that theSabinos cave population is part of a unique cave lineage unrelated to other A. mexicansus populations. Expand
Phylogeography, genetic structure, and gene flow in the endemic freshwater shrimp Palaemonetes suttkusi from Cuatro Ciénegas, Mexico
TLDR
It is recommended that the upper parts of the Río Salado, the Pozas Azules area, and the rest of the Cuatro Ciénegas basin should each be considered independent evolutionarily significant units for conservation, and that migration of species through human-made canals should be monitored and controlled. Expand
AGE AND POLYPHYLETIC ORIGINS OF HYBRID AND SPONTANEOUS PARTHENOGENETIC CAMPELOMA (GASTROPODA: VIVIPARIDAE) FROM THE SOUTHEASTERN UNITED STATES
TLDR
Analysis of mtDNA sequence variation from southeastern United States populations of the freshwater snail Campeloma shows patterns consistent with higher dispersal rates and recent range expansion of parthenogens, which should reduce the effects of mutation accumulation or parasitism. Expand
Thinning Reduces the Effect of Rust Infection on Jewelweed (Impatiens Capensis)
TLDR
It is found that the effect of infection depends on plant density, and interactions between competition and disease are likely to be important to the pop- ulation biology and breeding-system evolution of plants. Expand
Estimation of Hybridization and Introgression Frequency in Toads (Genus: Bufo) Using DNA Sequence Variation at Mitochondrial and Nuclear Loci
TLDR
Use of mitochondrial and nuclear molecular markers allowed unambiguous identification of hybrids and their maternal parent that could not have been performed without the use of both datasets, and phylogenetic relationships among B. fowleri and its close relatives in the B. americanus species complex were investigated. Expand
CONTRASTING PATTERNS OF SYNONYMOUS AND NONSYNONYMOUS SEQUENCE EVOLUTION IN ASEXUAL AND SEXUAL FRESHWATER SNAIL LINEAGES
TLDR
Findings suggest that patterns of synonymous and nonsynonymous nucleotide polymorphism in asexual snail lineages may be shaped by both severe founder effect and relaxed purifying selection. Expand
Spatial Geographic Mosaic in an Aquatic Predator-Prey Network
The geographic mosaic theory of coevolution predicts 1) spatial variation in predatory structures as well as prey defensive traits, and 2) trait matching in some areas and trait mismatching in othersExpand
Spatial mosaic evolution of snail defensive traits
TLDR
No autocorrelation among populations at small geographic and genetic distances for the two defensive traits of M. churinceanus were found and there was also no correlation between abiotic variables (temperature and conductivity) and snail defensive traits. Expand
GEOGRAPHIC RANGES, POPULATION STRUCTURE, AND AGES OF SEXUAL AND PARTHENOGENETIC SNAIL LINEAGES
  • Steven G. Johnson
  • Biology, Medicine
  • Evolution; international journal of organic…
  • 1 July 2006
TLDR
The results suggest that asexual lineages may persist in the short term through dispersal, and that various constraints may cause geographic restriction of sexual lineagess. Expand
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