Temporal and spatial patterns of allele and genotype frequencies at the Ng locus in blue grouse (Dendragapus obscurus)

The frequency of alleles and genotypes at the Ng locus in blue grouse from nine populations on Vancouver Island and the adjacent mainland was examined in an effort to detect systematic variations. There were no significant variations in allele frequencies between populations. Three of the nine populations sampled had significant departures from Hardy-Weinberg equilibrium conditions. Samples of four different cohorts indicated no significant shifts in allele or genotype frequencies between cohorts. These data, combined with other observations, suggest that the alleles at this locus are being maintained by selection. Thus, the utility of this locus as a marker in population studies is strengthened.

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A test for Hardy-Weinberg equilibrium on the X chromosome for sex-biased admixed populations

10.1101/552794 ◽

2019 ◽

Author(s):

Daniel Backenroth ◽

Shai Carmi

Keyword(s):

X Chromosome ◽

Random Mating ◽

Allele Frequencies ◽

Ratio Test ◽

Weinberg Equilibrium ◽

Genotype Frequencies ◽

Genome Wide ◽

Control Step ◽

Hardy Weinberg Equilibrium ◽

Males And Females

AbstractGenome-wide scans for deviations from Hardy-Weinberg equilibrium (HWE) are commonly applied to detect genotyping errors. In contrast to the autosomes, genotype frequencies on the X chromosome do not reach HWE within a single generation. Instead, if allele frequencies in males and females initially differ, they oscillate for a few generations towards equilibrium. Several populations world-wide have experienced recent sex-biased admixture, namely, their male and female founders differed in ancestry and thus in allele frequencies. Sex-biased admixture makes testing for HWE difficult on X, because deviations are naturally expected, even under random mating post-admixture and error-free genotyping. In this paper, we develop a likelihood ratio test and a χ2 test that detect deviations from HWE on X while allowing for natural deviations due to sex-biased admixture. We demonstrate by simulations that our tests are powerful for detecting deviations due to non-random mating, while at the same time they do not reject the null under historical sex-biased admixture and random mating thereafter. We also demonstrate that when applied to 1000 Genomes project populations (e.g., as a quality control step), our tests reject fewer SNPs (among those showing frequency differences between the sexes) than other tests.

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Isozyme variation in quaking aspen in Minnesota

Canadian Journal of Forest Research ◽

10.1139/x92-068 ◽

1992 ◽

Vol 22 (4) ◽

pp. 521-524 ◽

Cited By ~ 19

Author(s):

Steven T. Lund ◽

Glenn R. Furnier ◽

Carl A. Mohn

Keyword(s):

Gene Flow ◽

Mating System ◽

Allele Frequencies ◽

Quaking Aspen ◽

Isozyme Variation ◽

Weinberg Equilibrium ◽

Genotype Frequencies ◽

Hardy Weinberg Equilibrium ◽

Isozyme Loci

Variation at 10 polymorphic isozyme loci was examined for nine populations of quaking aspen (Populustremuloides Michx.) in Minnesota. Mean observed and expected estimates of isozyme heterozygosity were 0.217 and 0.220, respectively, with no significant differences in allele frequencies among populations and no significant deviations from genotype frequencies expected under Hardy–Weinberg equilibrium. These results suggest relatively high levels of gene flow among populations and a mating system involving little inbreeding.

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Hawk kite as potential bird scare device (the case of pigeons and grain processing factory)

Ukrainian Journal of Ecology ◽

10.15421/2018_350 ◽

2018 ◽

Vol 8 (2) ◽

pp. 334-336

Author(s):

A. V. Matsyura

Keyword(s):

Spatial Patterns ◽

Repellent Effect ◽

Preliminary Results ◽

Temporal And Spatial Patterns ◽

Grain Processing ◽

Feral Pigeons ◽

Temporal And Spatial ◽

Bird Behavior ◽

Hooded Crows

Here we presented the preliminary results of hawk kite usage against the feral pigeons in some grain processing factory. We studied the temporal and spatial patterns of repellent effect and bird behavior. We suggested the feral pigeons gradually increase the level of tolerance towards the hawk kite if no additional repellent measures were undertaken. Moreover, even initially the feral pigeons demonstrate higher tolerance towards the hawk kite compared to the Rooks or Hooded Crows.

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