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- Jarvis, Erich D., et al.
(författare)
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Phylogenomic analyses data of the avian phylogenomics project
- 2015
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Ingår i: GigaScience. - : Oxford University Press (OUP). - 2047-217X. ; 4
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Tidskriftsartikel (refereegranskat)abstract
- Background: Determining the evolutionary relationships among the major lineages of extant birds has been one of the biggest challenges in systematic biology. To address this challenge, we assembled or collected the genomes of 48 avian species spanning most orders of birds, including all Neognathae and two of the five Palaeognathae orders. We used these genomes to construct a genome-scale avian phylogenetic tree and perform comparative genomic analyses. Findings: Here we present the datasets associated with the phylogenomic analyses, which include sequence alignment files consisting of nucleotides, amino acids, indels, and transposable elements, as well as tree files containing gene trees and species trees. Inferring an accurate phylogeny required generating: 1) A well annotated data set across species based on genome synteny; 2) Alignments with unaligned or incorrectly overaligned sequences filtered out; and 3) Diverse data sets, including genes and their inferred trees, indels, and transposable elements. Our total evidence nucleotide tree (TENT) data set (consisting of exons, introns, and UCEs) gave what we consider our most reliable species tree when using the concatenation-based ExaML algorithm or when using statistical binning with the coalescence-based MP-EST algorithm (which we refer to as MP-EST*). Other data sets, such as the coding sequence of some exons, revealed other properties of genome evolution, namely convergence. Conclusions: The Avian Phylogenomics Project is the largest vertebrate phylogenomics project to date that we are aware of. The sequence, alignment, and tree data are expected to accelerate analyses in phylogenomics and other related areas.
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| 2. |
- Mugal, Carina F, et al.
(författare)
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GC-biased gene conversion links the recombination landscape and demography to genomic base composition : GC-biased gene conversion drives genomic base composition across a wide range of species
- 2015
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Ingår i: Bioessays. - : Wiley. - 0265-9247 .- 1521-1878. ; 37:12, s. 1317-1326
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Tidskriftsartikel (refereegranskat)abstract
- The origin and evolutionary dynamics of the spatial heterogeneity in genomic base composition have been debated since its discovery in the 1970s. With the recent availability of numerous genome sequences from a wide range of species it has been possible to address this question from a comparative perspective, and similarities and differences in base composition between groups of organisms are becoming evident. Ample evidence suggests that the contrasting dynamics of base composition are driven by GC-biased gene conversion (gBGC), a process that is associated with meiotic recombination. In line with this hypothesis, base composition is associated with the rate of recombination and the evolutionary dynamics of the recombination landscape, therefore, governs base composition. In addition, and at first sight perhaps surprisingly, the relationship between demography and genomic base composition is in agreement with the gBGC hypothesis: organisms with larger populations have higher GC content than those with smaller populations.
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