Neolithic Hedgehogs (Erinaceus europaeus) from the Island of Gotland show early contacts with the Swedish mainland

Previous research probing early migrations and contacts in the Baltic Sea area is characterized by the analysis of different chronologies and subsistent strategies on all sides of the Sea. Several studies performed on artifact typology, ceramics, grave rituals and physical anthropology ended with varying results. Although the question of human origins remains inconclusive, in this study, we rely on the phylogeography of an animal associated with humans to elucidate findings regarding prehistoric human migration and contacts.Hedgehogs, along with other fauna on Gotland, were brought over to the island by humans. We examined hedgehog mitochondrial DNA from the Pitted Ware Culture (Middle Neolithic). The genetic signatures of the animals on the island were investigated to determine the animal’s origin.From the 23 bones originally examined, twelve bones from all five locations studied yielded reliable results and resembled published extant Erinaceus europaeus sequences from Sweden, Norway and Denmark. We postulate that a western heritage for the Neolithic hedgehogs on Gotland indicates early human contact with the Swedish mainland.     

Genetic analysis of wheat landraces enables the location of the first agricultural sites in Italy to be identified

We typed five microsatellite loci in 52 landraces of Italian emmer wheat to determine if genetic analysis of cereals can provide information relevant to the spread of agriculture. Each of the five loci was polymorphic with 43 allele combinations identified in the 52 landraces. The allele combinations fell into two groups. Group 1 comprised 27 genotypes found in 42 landraces and Group 2 comprised 15 genotypes found in 10 landraces. The landraces with Group 1 genotypes showed a strong correlation between geographical and genetic distances (r = 0.601, p < 0.001) but those with Group 2 genotypes did not (r = 0.116, p = 0.244). We inferred that the Group 1 landraces might therefore retain a phylogeographical structure that reflects ancient events. We present a phylogeographical model for the spread of agriculture that enables the point of origin of crop cultivation to be predicted by comparison between the genetic and geographical distances between landraces. We applied this model to the Group 1 landraces by positioning 131 hypothetical points of origin around the coastline and northern border of Italy. The highest correlation coefficients between genetic and geographical distances were seen for hypothetical points of origin located on the coast of northern Puglia. We repeated the analysis with 1040 hypothetical points of origin located within the Italian peninsula. Again, the highest correlation coefficients were located in northern Puglia. These predicted points of origin correspond with the location of the earliest agricultural sites in Italy. The results show that plant genetics can be used to study the spread of agriculture.     

Ancient-DNA reveals an Asian type of Mycobacterium leprae in medieval Scandinavia

Leprosy is a chronic infection of the skin and peripheral nerves caused by the pathogen Mycobacterium leprae. Its impact on human populations and societies of the past as well as its phylogeographic patterns around the world – at least in modern times – has been well documented. This slow growing bacterium has been shown to exist in distinct ‘SNP types’ that occur in relatively defined parts of the globe. The routes that the disease followed in the past are, however, still uncertain. This study of ancient-DNA typing of archaeological human remains from Sweden dated to early Medieval times provides genetic evidence that a transmission of M. leprae ‘SNP subtype’ 2G – found mainly in Asia – took or had already taken place at that time from the Middle East to Scandinavia. This finding is unique in the history of leprosy in Europe. All human specimens from this continent – both modern and ancient – that have been tested to date showed that the one responsible for the infection strains of M. leprae belong to ‘SNP type’ 3, whereas our results show that there were some European populations that were hosts to bacteria representing ‘SNP type’ 2 of the species as well.     

Ancient DNA typing of archaeological pig remains corroborates historical records

The recent increase in both the abundance and taxonomic range of DNA sequence data in public repositories makes it possible to determine the maternal origin of lineages of faunal archaeological material by characterizing its mitochondrial DNA. Among the most commonly represented taxa are domesticated animals, for which extensive genetic characterization has revealed high levels of genetic diversity and (in at least some cases) strong phylogeographic clustering. Such information has significant implications not only for characterizing important aspects of the occupation history of archaeological sites, but also in providing novel insights into colonisation history and the scale and scope of trade and exchange networks. This can be done through studying the origins and dispersal of proxy organisms such as commensal and domesticated animals, as well as economically important wild fauna. To illustrate this approach, we compare historical records of maritime movement of people and pigs from two sites on Lord Howe Island, Australia, to phylogeographic results of DNA extracted from pig bones.