Demographic reconstruction from ancient DNA supports rapid extinction of the great auk

The great auk was once abundant and distributed across the North Atlantic. It is now extinct, having been heavily exploited for its eggs, meat, and feathers. We investigated the impact of human hunting on its demise by integrating genetic data, GPS-based ocean current data, and analyses of population viability. We sequenced complete mitochondrial genomes of 41 individuals from across the species’ geographic range and reconstructed population structure and population dynamics throughout the Holocene. Taken together, our data do not provide any evidence that great auks were at risk of extinction prior to the onset of intensive human hunting in the early 16th century. In addition, our population viability analyses reveal that even if the great auk had not been under threat by environmental change, human hunting alone could have been sufficient to cause its extinction. Our results emphasise the vulnerability of even abundant and widespread species to intense and localised exploitation

Detecting the medieval cod trade: a new method and first results

This paper explores the potential of stable isotope analysis to identify the approximate region of catch of cod by analysing bones from medieval settlements in northern and western Europe. It measures the d13C and d15N values of cod bone collagen from medieval control samples collected from sites around Arctic Norway, the North Sea, the Kattegat and the Baltic Sea. These data were considered likely to differ by region due to, for example, variation in the length of the food chain, water temperature and salinity. We find that geographical structuring is indeed evident, making it possible to identify bones from cod caught in distant waters. These results provide a new methodology for studying the growth of long-range trade in dried cod and the related expansion of fishing effort—important aspects of the development of commercialisation in medieval Europe. As a first test of the method, we analyse three collections of cod bones tentatively interpreted as imported dried fish based on a priori zooarchaeological criteria. The results tentatively suggest that cod were being transported or traded over very long distances since the end of the first millennium AD

Flexibility and diversity in subsistence during the late Mesolithic: faunal evidence from Asnæs Havnemark

In 2007, excavations at the late Mesolithic (Ertebølle) coastal site of Asnæs Havnemark recovered a wealth of flint, bone, and ceramic artefacts. A comprehensive analysis of the faunal remains resulted in over 50,000 identified specimens. Roe deer and gadids predominate, but there are a wide variety of other species represented. Stable isotope analyses of dog bones point to the importance of marine resources. Oxygen isotope analyses of otoliths indicate that fishing was conducted in multiple seasons of the year. Comparison with other late Mesolithic sites demonstrates that while generally the same species of animals were exploited everywhere, there are major differences in the relative abundances of species. The broad subsistence base available and flexibility in how it was exploited weaken arguments for a subsistence crisis brought on by environmental stresses as the causal mechanism for the adoption of domesticated plants and animals at the onset of theNeolithic