Restricted range size brings about noteworthy genetic consequences that may affect the viability of a population and eventually its extinction. Particularly, the question if an increase in inbreeding can avert the accumulation of genetic load via purging is hotly debated in the conservation genetic field. Insular populations with limited range sizes represent an ideal setup for relating range size to these genetic factors. Leveraging a set of eight differently sized populations of Galápagos mockingbirds (Mimus), we investigated how island size shaped effective population size (Ne), inbreeding and genetic load. We assembled a genome of M. melanotis and genotyped three individuals per population by whole-genome resequencing. Demographic inference showed that the Ne of most populations remained high after the colonisation of the archipelago 1-2 Mya. Ne decline in M. parvulus happened only 10-20 Kya, whereas the critically endangered M. trifasciatus showed a longer history of reduced Ne. Despite these historical fluctuations, the current island size determines Ne in a linear fashion. In contrast, significant inbreeding coefficients, derived from runs of homozygosity, were identified only in the four smallest populations. The index of additive genetic load suggested purging in M. parvulus, where the smallest populations showed the lowest load. By contrast, M. trifasciatus carried the highest genetic load, possibly due to a recent rapid bottleneck. Overall, our study demonstrates a complex effect of demography on inbreeding and genetic load, providing implications in conservation genetics in general and in a conservation project of M. trifasciatus in particular.

• Klíčová slova
• conservation genetics, demographic inference, genetic diversity, genetic load,
• MeSH
• genetická zátěž * MeSH
• genom * MeSH
• genotyp MeSH
• hustota populace MeSH
• inbreeding * MeSH
• ostrovy MeSH
• Passeriformes * genetika   MeSH
• populační genetika * MeSH
• zachování přírodních zdrojů MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Ekvádor MeSH
• ostrovy MeSH

Animal microbiomes play an important role in dietary adaptation, yet the extent to which microbiome changes exhibit parallel evolution is unclear. Of particular interest is an adaptation to extreme diets, such as blood, which poses special challenges in its content of proteins and lack of essential nutrients. In this study, we assessed taxonomic signatures (by 16S rRNA amplicon profiling) and potential functional signatures (inferred by Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt)) of haematophagy in birds and bats. Our goal was to test three alternative hypotheses: no convergence of microbiomes, convergence in taxonomy and convergence in function. We find a statistically significant effect of haematophagy in terms of microbial taxonomic convergence across the blood-feeding bats and birds, although this effect is small compared to the differences found between haematophagous and non-haematophagous species within the two host clades. We also find some evidence of convergence at the predicted functional level, although it is possible that the lack of metagenomic data and the poor representation of microbial lineages adapted to haematophagy in genome databases limit the power of this approach. The results provide a paradigm for exploring convergent microbiome evolution replicated with independent contrasts in different host lineages. This article is part of the theme issue 'Convergent evolution in the genomics era: new insights and directions'.

• Klíčová slova
• convergence, haematophagy, microbiome,
• MeSH
• Bacteria klasifikace   genetika   izolace a purifikace   MeSH
• biologická evoluce MeSH
• Chiroptera genetika   mikrobiologie   fyziologie   MeSH
• DNA bakterií genetika   MeSH
• fylogeneze MeSH
• ptáci genetika   mikrobiologie   fyziologie   MeSH
• RNA ribozomální 16S genetika   MeSH
• stravovací zvyklosti MeSH
• střevní mikroflóra * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• DNA bakterií MeSH
• RNA ribozomální 16S MeSH