The Small and the Dead: A Review of Ancient DNA Studies Analysing Micromammal Species

Introduced and extinct: neglected archival specimens shed new light on the historical biogeography of an iconic avian species in the Mediterranean

Collection specimens provide valuable and often overlooked biological material that enables addressing relevant, long-unanswered questions in conservation biology, historical biogeography, and other research fields. Here, we use preserved specimens to analyze the historical distribution of the black francolin (Francolinus francolinus, Phasianidae), a case that has recently aroused the interest of archeozoologists and evolutionary biologists. The black francolin currently ranges from the Eastern Mediterranean and the Middle East to the Indian subcontinent, but, at least since the Middle Ages, it also had a circum-Mediterranean distribution. The species could have persisted in Greece and the Maghreb until the 19th century, even though this possibility had been questioned due to the absence of museum specimens and scant literary evidence. Nevertheless, we identified four 200-year-old stuffed black francolins-presumably the only ones still existing-from these areas and sequenced their mitochondrial DNA control region. Based on the comparison with conspecifics (n = 396) spanning the entirety of the historic and current species range, we found that the new samples pertain to previously identified genetic groups from either the Near East or the Indian subcontinent. While disproving the former occurrence of an allegedly native westernmost subspecies, these results point toward the role of the Crown of Aragon in the circum-Mediterranean expansion of the black francolin, including the Maghreb and Greece. Genetic evidence hints at the long-distance transport of these birds along the Silk Road, probably to be traded in the commerce centers of the Eastern Mediterranean.

Microsatellite based assignment reveals history of extirpated mountain ungulate

During the early 1900s, Northern chamois (Rupicapra rupicapra) populations in the northern Dinaric Mountains were extirpated. During the 1960s and 1970s there were several reintroductions of individuals from two Northern chamois subspecies (Alpine chamois, R. r. rupicapra and Balkan chamois, R. r. balcanica) from neighbouring areas in the attempt to re-establish the population. Accurate taxonomic classification, at subspecies level, of the autochthonous extirpated population was not known. To clarify which subspecies was present before reintroduction, we genotyped four male chamois skulls originating from Velebit Mountain, collected around 25 years before the population local extinction. DNA was successfully extracted from middle layer and outer sheath of horns. Assignment based on microsatellite loci, using both Bayesian clustering in STRUCTURE (with q values between 0.55 and 0.73) and DAPC (with individual membership probabilities of 0.99 and 1.00) indicated higher assessed likelihood for the Alpine subspecies.

Mitogenomics of historical type specimens of Australasian turtles: clarification of taxonomic confusion and old mitochondrial introgression

Diagnosability is central to taxonomy as are type specimens which define taxa. New advances in technologies and the discovery of new informative traits must be matched with previous taxonomic decisions based on name-bearing type specimens. Consequently, the challenge of sequencing highly degraded DNA from historical types becomes an inevitability to resolve the very many taxonomic issues arising from, by modern standards, poor historical species descriptions leading to difficulties to assign names to genetic clusters identified from fresh material. Here we apply high-throughput parallel sequencing and sequence baiting to reconstruct the mitogenomes from 18 type specimens of Australasian side-necked turtles (Chelidae). We resolve a number of important issues that have confused the taxonomy of this family, and analyse the mitogenomes of the types and those of fresh material to improve our understanding of the phylogenetic relationships of this morphologically conservative group. Together with previously published nuclear genomic data, our study provides evidence for multiple old mitochondrial introgressions.

How to integrate wet lab and bioinformatics procedures for wine DNA admixture analysis and compositional profiling: Case studies and perspectives

The varietal authentication of wines is fundamental for assessing wine quality, and it is part of its compositional profiling. The availability of historical, cultural and chemical composition information is extremely important for quality evaluation. DNA-based techniques are a powerful tool for proving the varietal composition of a wine. SSR-amplification of genomic residual Vitis vinifera DNA, namely Wine DNA Fingerprinting (WDF) is able to produce strong, analytical evidence concerning the monovarietal nature of a wine, and for blended wines by generating the probability of the presence/absence of a certain variety, all in association with a dedicated bioinformatics elaboration of genotypes associated with possible varietal candidates. Together with WDF we could exploit Bioinformatics techniques, due to the number of grape genomes grown. In this paper, the use of WDF and the development of a bioinformatics tool for allelic data validation, retrieved from the amplification of 7 to 10 SSRs markers in the Vitis vinifera genome, are reported. The wines were chosen based on increasing complexity; from monovarietal, experimental ones, to commercial monovarietals, to blended commercial wines. The results demonstrate that WDF, after calculation of different distance matrices and Neighbor-Joining input data, followed by Principal Component Analysis (PCA) can effectively describe the varietal nature of wines. In the unknown blended wines the WDF profiles were compared to possible varietal candidates (Merlot, Pinot Noir, Cabernet Sauvignon and Zinfandel), and the output graphs show the most probable varieties used in the blend as closeness to the tested wine. This pioneering work should be meant as to favor in perspective the multidisciplinary building-up of on-line databanks and bioinformatics toolkits on wine. The paper concludes with a discussion on an integrated decision support system based on bioinformatics, chemistry and cultural data to assess wine quality.