Anthropo-Demographic Study Among the Caste and Tribal Groups of Central Himalayas: 4. Selection Intensities

Abstract Methods for simulating samples and sample statistics, under mutation-selection-drift equilibrium for a class of nonneutral population genetics models, and for evaluating the likelihood surface, in selection and mutation parameters, are developed and applied for observed data. The methods apply to large populations in settings in which selection is weak, in the sense that selection intensities, like mutation rates, are of the order of the inverse of the population size. General diploid selection is allowed, but the approach is currently restricted to models, such as the infinite alleles model and certain K-models, in which the type of a mutant allele does not depend on the type of its progenitor allele. The simulation methods have considerable advantages over available alternatives. No other methods currently seem practicable for approximating likelihood surfaces.

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Potential distribution of oak forests in the central Himalayas and implications for future ecosystem services supply to rural communities

Ecosystem Services ◽

10.1016/j.ecoser.2021.101310 ◽

2021 ◽

Vol 50 ◽

pp. 101310

Author(s):

Niyati Naudiyal ◽

Joachim Schmerbeck

Keyword(s):

Ecosystem Services ◽

Rural Communities ◽

Potential Distribution ◽

Oak Forests ◽

Central Himalayas

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Selection on Rapidly Evolving Proteins in the Arabidopsis Genome

Genetics ◽

10.1093/genetics/163.2.723 ◽

2003 ◽

Vol 163 (2) ◽

pp. 723-733 ◽

Cited By ~ 1

Author(s):

Marianne Barrier ◽

Carlos D Bustamante ◽

Jiaye Yu ◽

Michael D Purugganan

Keyword(s):

Expressed Sequence Tag ◽

Amino Acid Replacement ◽

Adaptive Divergence ◽

Coding Region ◽

Protein Coding ◽

Hierarchical Bayesian Analysis ◽

Brassicaceae Species ◽

Replacement Site ◽

Orthologous Loci ◽

Selection Intensities

Abstract Genes that have undergone positive or diversifying selection are likely to be associated with adaptive divergence between species. One indicator of adaptive selection at the molecular level is an excess of amino acid replacement fixed differences per replacement site relative to the number of synonymous fixed differences per synonymous site (ω = Ka/Ks). We used an evolutionary expressed sequence tag (EST) approach to estimate the distribution of ω among 304 orthologous loci between Arabidopsis thaliana and A. lyrata to identify genes potentially involved in the adaptive divergence between these two Brassicaceae species. We find that 14 of 304 genes (∼5%) have an estimated ω > 1 and are candidates for genes with increased selection intensities. Molecular population genetic analyses of 6 of these rapidly evolving protein loci indicate that, despite their high levels of between-species nonsynonymous divergence, these genes do not have elevated levels of intraspecific replacement polymorphisms compared to previously studied genes. A hierarchical Bayesian analysis of protein-coding region evolution within and between species also indicates that the selection intensities of these genes are elevated compared to previously studied A. thaliana nuclear loci.

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