As the first domestic species, dogs likely dispersed with different cultural groups during the Late Pleistocene and Holocene. To test this hypothesis, we analyzed 73 ancient dog genomes, including 17 newly sequenced individuals sampled from East Asia to the West Eurasian Steppe spanning nearly 10,000 years. Our results indicate correlations between the ancestry of dogs and specific ancient human populations from eastern Europe to Eastern Siberia, including Ancient Paleo-Siberians, Eastern hunter-gatherers, East Asians, and Steppe pastoralists. We also identify multiple shifts in the ancestry of dogs that coincide with specific dispersals of hunter-gatherers, farmers, and pastoralists. Combined, our results reveal the long-term and integral role that dogs played in a multitude of human societies.

Dogs exhibit an exceptional range of morphological diversity as a result of their long-term association with humans. Attempts to identify when dog morphological variation began to expand have been constrained by the limited number of Pleistocene specimens, the fragmentary nature of remains, and difficulties in distinguishing early dogs from wolves on the basis of skeletal morphology. In this study, we used three-dimensional geometric morphometrics to analyze the size and shape of 643 canid crania spanning the past 50,000 years. Our analyses show that a distinctive dog morphology first appeared at about 11,000 calibrated years before present, and substantial phenotypic diversity already existed in early Holocene dogs. Thus, this variation emerged many millennia before the intense human-mediated selection shaping modern dog breeds beginning in the 19th century.

The earliest morphologically identifiable dogs are from Europe and date to at least 14,000 years ago ^1–5 , although early remains are also found in other regions. The origin of early dogs in Europe, and their relationships to other dogs, has remained elusive in the absence of genome-wide data. Similarly, although dogs were the only domestic animal to predate agriculture, little is known about how the arrival of Neolithic farmers from Southwest Asia affected the dogs living with European Mesolithic hunter-gatherers. Here we analysed 216 canid remains, including 181 from Palaeolithic and Mesolithic Europe. We developed a genome-wide capture approach that enriched endogenous DNA by 10–100-fold and could distinguish dog from wolf ancestry for 141 of 216 remains. The oldest dog data that we recovered are from a 14,200-year-old dog from the Kesslerloch site in Switzerland, and we find that it shares ancestry with later worldwide dogs—inconsistent with the hypothesis that European Upper Palaeolithic dogs derived wholly from a separate domestication process. The Kesslerloch dog already displays more affinity to Mesolithic, Neolithic and present-day European dogs than to Asian dogs, demonstrating that dog genetic diversification had started well before 14,200 years ago. We find a Neolithic influx of Southwest Asian ancestry into Europe, but this seems to have been of smaller magnitude than in humans, suggesting that Mesolithic dogs contributed substantially to Neolithic, and, ultimately, probably also modern, European dogs.

Starting four decades ago, studies have examined the ecology and evolutionary dynamics of populations and species using short mitochondrial DNA fragments and stable isotopes. Through technological and analytical advances, the methods and biomolecules at our disposal have increased significantly to now include lipids, whole genomes, proteomes, and even epigenomes. At an unprecedented resolution, the study of ancient biomolecules has made it possible for us to disentangle the complex processes that shaped the ancient faunal diversity across millennia, with the potential to aid in implicating probable causes of species extinction and how humans impacted the genetics and ecology of wild and domestic species. However, even now, few studies explore interdisciplinary biomolecular approaches to reveal ancient faunal diversity dynamics in relation to environmental and anthropogenic impact. This review will approach how biomolecules have been implemented in a broad variety of topics and species, from the extinct Pleistocene megafauna to ancient wild and domestic stocks, as well as how their future use has the potential to offer an enhanced understanding of drivers of past faunal diversity on Earth.

We compared the responses of rat stomach ornithine decarboxylase (ODC) and histidine decarboxylase (HDC) to food intake, oral treatment with antisecretagogues, NaHCO3, and hypertonic NaCl, antrectomy, intravenous infusion of gastrin-17, the selective cholecystokinin (CCK)-B/gastrin receptor antagonist L-365,260, and the somatostatin analogue RC-160. The serum gastrin concentration and oxyntic mucosal ODC and HDC activities were higher in freely fed rats than in fasted rats. Food intake in fasted rats raised the serum gastrin concentration and the ODC and HDC activities. Ranitidine, omeprazole, and NaHCO3 raised the serum gastrin concentration and activated ODC and HDC. Hypertonic NaCl raised the ODC activity 200-fold, whereas circulating gastrin and HDC activity were increased only moderately. Infusion of gastrin-17 activated HDC but not ODC. L-365,260 prevented the activation of HDC but not of ODC in response to food intake and treatment with omeprazole, NaHCO3, or hypertonic NaCl. Antrectomy prevented the food- and omeprazole-evoked rise in oxyntic mucosal HDC activity but not the rise in ODC activity. RC-160 suppressed HDC activity after food intake and treatment with omeprazole, NaHCO3, or NaCl. In contrast, RC-160 suppressed omeprazole- and NaHCO3-evoked ODC activation but not that evoked by food intake or NaCl. The results support the view that HDC in the oxyntic mucosa is activated by gastrin and suppressed by somatostatin. The induction of ODC is not mediated by gastrin; ODC activation appears to be related to acid inhibition per se or to mucosal maintenance and repair; somatostatin, or rather the lack of it, might contribute to the induction of ODC after acid blockade. The mechanism behind the activation of rat stomach ODC seems to differ depending on the type of stimulus.