Distribution, Abundance and Population Structuring of Beaked Wales in the Great Bahama Canyon, Northern Bahamas

As a consequence of genetic studies of population structuring, the usefulness of subspecies has been questioned, with opinions divided. The situation is further confused by the use of varying species and subspecies concepts. Most alternatives require each taxon to be following an independent evolutionary trajectory. These include traditional approaches and the more recent phylogenetic species concept. The latter has led to large increases in the apparent number of taxa in some groups, though strong objections have been raised to this approach. An alternative, the ecological species concept, has been opposed by phylogeneticists. These two approaches are compared using morphological and genetic data from common wallaroo (Osphranter robustus) populations. The different taxonomies that might result (many species, one species with two subspecies, one species with no subspecies) can have significant consequences for legislative and management decisions. The ecological approach is considered preferable for subspecies and the present taxonomy is maintained. A potential location of the boundary between the wallaroo subspecies is proposed. How the use of the different subspecies definitions would affect legislative decisions is explored.

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Population structuring of the endemic black-cheeked gnateater, Conopophaga melanops melanops (Vieillot, 1818) (Aves, Conopophagidae), in the Brazilian Atlantic Forest

Brazilian Journal of Biology ◽

10.1590/s1519-69842007000500009 ◽

2007 ◽

Vol 67 (4 suppl) ◽

pp. 867-872 ◽

Cited By ~ 2

Author(s):

VO. Lunardi ◽

MR. Francisco ◽

PM. Galetti Jr.

Keyword(s):

Genetic Differentiation ◽

Atlantic Forest ◽

Rapd Markers ◽

Nonparametric Test ◽

Brazilian Atlantic Forest ◽

Randomly Amplified Polymorphic Dna ◽

Molecular Variance ◽

Local Populations ◽

Population Structuring ◽

Significant Genetic Divergence

Randomly amplified polymorphic DNA (RAPD) markers were used to analyze genetic differentiation among three populations of the endemic Black-cheeked Gnateater (Conopophaga melanops melanops) within a larger pristine reminiscent of the Brazilian Atlantic Forest. Analyses of molecular variance (AMOVA) (phiST = 0.13149, P < 0.0001) and the nonparametric test for homogeneity of the molecular variance (HOMOVA) (B = 0.32337; P = 0.0019) showed a statistically significant genetic divergence among the three Black-cheeked Gnateater populations in a continuous transect of 250 km. Some hypothetic explanations for these results are the sedentary nature of the species and the historical isolation of the populations in refuges during the Pleistocene. The present results suggest that the local populations were naturally differentiated along the entire original range before the recent process of massive deforestation.

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Genetic diversity and population structure among goat genotypes in Kenya

10.1101/2020.07.06.189290 ◽

2020 ◽

Author(s):

Ruth W. Waineina ◽

Kiplangat Ngeno ◽

Tobias O. Otieno ◽

Evans D. Ilatsia

Keyword(s):

Population Structure ◽

Principal Component ◽

Genetic Distances ◽

Snp Markers ◽

Founder Population ◽

Good Opportunity ◽

Model Based Clustering ◽

Population Structuring ◽

Improvement Programs ◽

Genotype Clustering

AbstractPopulation structure and relationship information among goats is critical for genetic improvement, utilization and conservation. This study explored population structure and level of gene intermixing among four goat genotypes in Kenya: Alpine (n = 30), Toggenburg (n = 28), Saanen (n = 24) and Galla (n = 12). The population structuring and relatedness were estimated using principal component analysis utilizing allele frequencies of the SNP markers. Genotype relationships were evaluated based on the calculated Reynolds genetic distances. A phylogenetic tree was constructed to represent genotype clustering using iTOL software. Population structure was investigated using model-based clustering (ADMIXTURE) Genotypes relationships revealed four distinctive clusters: Alpine, Galla, Saanen and Toggenburg. The ADMIXTURE results revealed some level of gene intermixing among Alpine, Toggenburg and Saanen with Galla. Saanen goats were the most admixed genotype with 84%, 7% and 4% of its genome derived from Galla, Alpine and Toggenburg respectively. Alpine and Toggenburg goats shared some associations with the Galla goat; 10% and 1% respectively. The association of Galla with other genotypes was anticipated since Galla goat was used as the founder population for crossbreeding with Saanen, Alpine and Toggenburg breed. The genetic variations among the goat genotypes observed, will provide a good opportunity for sustainable utilization, conservation and future genetic resource improvement programs in goat genotypes in Kenya.

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