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Abstract The stone marten (Martes foina) is an important species for cytogenetic studies in the order Carnivora. ZooFISH probes created from its chromosomes provided a strong and clean signal in chromosome painting experiments and were valuable for studying the evolution of carnivoran genome architecture. The research revealed that the stone marten chromosome set is similar to the presumed ancestral karyotype of the Carnivora, which added an additional value for the species. Using linked-read and Hi-C sequencing, we generated a chromosome-length genome assembly of a male stone marten (Gansu province, China) from a primary cell line. The stone marten assembly had a length of 2.42 Gbp, scaffold N50 of 144 Mbp, and a 96.2% BUSCO completeness score. We identified 19 chromosomal scaffolds (2n = 38) and assigned them chromosome ids based on chromosome painting data. Annotation identified 20,087 protein-coding gene models, of which 18,283 were assigned common names. Comparison of the stone marten assembly with the cat, dog, and human genomes revealed several small syntenic blocks absent on the published painting maps. Finally, we assessed the heterozygosity and its distribution over the chromosomes. The detected low heterozygosity level (0.4 hetSNPs/kbp) and the presence of long runs of homozygosity require further research and a new evaluation of the conservation status of the stone marten in China. Combined with available carnivoran genomes in large-scale synteny analysis, the stone marten genome will highlight new features and events in carnivoran evolution, hidden from cytogenetic approaches. 

Abstract Despite tremendous efforts in the past decades, relationships among main avian lineages remain heavily debated without a clear resolution. Discrepancies have been attributed to diversity of species sampled, phylogenetic method and the choice of genomic regions^1–3. Here we address these issues by analysing the genomes of 363 bird species⁴(218 taxonomic families, 92% of total). Using intergenic regions and coalescent methods, we present a well-supported tree but also a marked degree of discordance. The tree confirms that Neoaves experienced rapid radiation at or near the Cretaceous–Palaeogene boundary. Sufficient loci rather than extensive taxon sampling were more effective in resolving difficult nodes. Remaining recalcitrant nodes involve species that are a challenge to model due to either extreme DNA composition, variable substitution rates, incomplete lineage sorting or complex evolutionary events such as ancient hybridization. Assessment of the effects of different genomic partitions showed high heterogeneity across the genome. We discovered sharp increases in effective population size, substitution rates and relative brain size following the Cretaceous–Palaeogene extinction event, supporting the hypothesis that emerging ecological opportunities catalysed the diversification of modern birds. The resulting phylogenetic estimate offers fresh insights into the rapid radiation of modern birds and provides a taxon-rich backbone tree for future comparative studies. 

Abstract The grey wolf (Canis lupus) was the first species to give rise to a domestic population, and they remained widespread throughout the last Ice Age when many other large mammal species went extinct. Little is known, however, about the history and possible extinction of past wolf populations or when and where the wolf progenitors of the present-day dog lineage (Canis familiaris) lived^1–8. Here we analysed 72 ancient wolf genomes spanning the last 100,000 years from Europe, Siberia and North America. We found that wolf populations were highly connected throughout the Late Pleistocene, with levels of differentiation an order of magnitude lower than they are today. This population connectivity allowed us to detect natural selection across the time series, including rapid fixation of mutations in the geneIFT8840,000–30,000 years ago. We show that dogs are overall more closely related to ancient wolves from eastern Eurasia than to those from western Eurasia, suggesting a domestication process in the east. However, we also found that dogs in the Near East and Africa derive up to half of their ancestry from a distinct population related to modern southwest Eurasian wolves, reflecting either an independent domestication process or admixture from local wolves. None of the analysed ancient wolf genomes is a direct match for either of these dog ancestries, meaning that the exact progenitor populations remain to be located.