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Parducci, L.

Publications and source records attributed to Parducci, L..

4 recordsLinked to original sources

Hic sunt dracones: ancient DNA from the extinct palaeofauna of the tiny Mediterranean archipelago of Columbretes and its implications for human visitation

The Columbretes archipelago in the Mediterranean is an example of deep isolation and sporadic human interaction during the Holocene. We recovered ancient DNA from 2,600-year-old microfauna and historical museum specimens to investigate the island's extinct fauna. Despite challenging preservation conditions, we successfully recovered mitogenomes from historical Vipera latastei specimens, and partial mitogenomes from snake, skink, and lizard subfossils. Phylogenetic analyses confirm the extinct Columbretes snake as Vipera latastei, sharing a haplotype with the historical specimen and clustering with modern populations from northeastern Iberia, validating its provenance and suggesting a single mitochondrial lineage since isolation. The extinct skink, Chalcides bedriagai, also shows affinities with eastern Iberia. These results point to a vicariant origin for the herpetofauna, likely isolated on the island following sea level rise after the Last Glacial Maximum. Conversely, a 2,600-year-old mouse incisor yielded a Mus musculus mitogenome, indicating Iron Age human-mediated introduction. Additionally, genomic analysis of a 11th-century CE human burial revealed an individual with genetic affinities to the Central Mediterranean and Balkans, highlighting medieval maritime mobility. This study resolves the long-debated Columbretes snake identity, traces biogeographic origins and illustrates the interplay of natural isolation and anthropogenic influence on the island biodiversity.

ecology↗

Lifestyle impacts the oral microbiome of Classical and Post-classical societies in Italy

ObjectivesThe fall of the Roman Empire (476 CE) profoundly affected the lives of its peoples due to the political, administrative, and territorial changes that occurred. The majority of written records of the time focus on the social elite, leaving larger parts of the population understudied. Here, we employ a bioarchaeological approach to understand how differences in lifestyle may be reflected in the oral microbiome of people from different social classes living before and after the fall. Material and MethodsWe analysed shotgun sequencing data from dental calculus, the preserved oral microbiome, of 67 individuals belonging to different social classes from two Classical cemeteries dated to I-III century CE (Lucus Feroniae and Isola Sacra) and one post-Classical cemetery dated to IV-VIII century CE (Selvicciola), all located in proximity to the city of Rome, Italy. ResultsWe detect significant differences in the oral microbiome taxonomic and functional composition across time periods and social classes, with the rural town of Lucus Feroniae standing out compared to its two counterparts. Reliable identification of dietary items was not possible. DiscussionThe distinct oral microbiome of Lucus Feroniae could reflect differences in general health and subsistence practices. The rural position of this community may have mitigated the cyclical food crises that, instead, affected the contemporary Isola Sacra and the later community of Selvicciola, thereby buffering against the nutritional stress observed in these two locations.

genomics↗

Genetic diversity and conservation insights for the baobab Adansonia suarezensis in northern Madagascar: a whole genome SNP analysis

Madagascar is home to seven unique baobab species in the genus Adansonia, all threatened by climate change, habitat destruction, and deforestation. Previous studies have highlighted the vulnerability of baobabs, particularly A. suarezensis, without delving into the specific genetic structure of its populations. In this paper we examine the genetic structure, diversity, and connectivity of seven populations of A. suarezensis, using genome-wide Single Nucleotide Polymorphism (SNP) data. The results revealed significant genetic differentiation between inland and coastal populations, with the Mahory population forming a distinct genetic cluster characterized by high heterozygosity but low polymorphism, indicative of historical bottlenecks. In contrast, northern populations showed greater admixture and gene flow but higher inbreeding coefficients in coastal regions, such as Ambilo and Cap dAmbre, suggesting localized inbreeding depression. Additionally, historical climatic shifts and potential anthropogenic dispersal are explored as contributing factors to the current genetic patterns. This study highlights the importance of understanding genetic dynamics for conservation, emphasizing habitat restoration and targeted management strategies to preserve the evolutionary potential of A. suarezensis and ensure its long-term survival.

genetics↗

Isolated Grauer's gorilla populations differ in diet and gut microbiome

The animal gut microbiome has been implicated in a number of key biological processes, ranging from digestion to behavior, and has also been suggested to facilitate local adaptation. However, studies in wild animals rarely compare multiple populations that differ ecologically, which is the level at which local adaptation may occur. Further, few studies simultaneously characterize diet and the gut microbiome from the same sample, despite the likely presence of co-dependencies. Here, we investigate the interplay between diet and gut microbiome in three geographically isolated populations of the critically endangered Grauers gorilla, which we show to be genetically differentiated. We find population- and social group-specific dietary and gut microbial profiles and co-variation between diet and gut microbiome, despite the presence of core microbial taxa. There was no detectable effect of age, sex, or genetic relatedness on the microbiome. Diet differed considerably across populations, with the high-altitude population consuming a lower diversity of plants compared to low-altitude populations, consistent with food plant availability constraining diet. The observed pattern of covariation between diet and gut microbiome is likely a result of long-term social and ecological factors. Our study suggests that the gut microbiome is sufficiently plastic to support flexible food selection and hence contribute to local adaptation.

ecology↗