The process and timing of initial dog domestication is an important topic in human evolution and one which has inspired much recent debate. Findings of putative domesticated dogs have recently been ...reported from two Gravettian sites by Germonpré et al. (2015a), joining a handful of other reputed “Paleolithic dogs” dating to before the Last Glacial Maximum (LGM). Though these findings have been challenged previously, this paper draws attention to the most significant shortcoming in claims of early domesticated dogs – a lack of data on Pleistocene wolf variation. Without comprehensive data on the range of variation within Pleistocene wolf populations, the identification of domesticated dogs from prior to the Late Upper Paleolithic cannot be conclusively accepted or rejected.
•The timing and location of dog domestication is still uncertain.•A handful of proposed Paleolithic (pre-16,000 BP) domesticated dog remains have been reported from Europe and Siberia, but are highly contested.•Very little Pleistocene wolf material has been analyzed for comparison to putative Paleolithic dogs.•Without comprehensive data on Pleistocene wolf variation, claims for Paleolithic domesticated dogs cannot be conclusively accepted or rejected.
Advances in the isolation and sequencing of ancient DNA have begun to reveal the population histories of both people and dogs. Over the last 10,000 y, the genetic signatures of ancient dog remains ...have been linked with known human dispersals in regions such as the Arctic and the remote Pacific. It is suspected, however, that this relationship has a much deeper antiquity, and that the tandem movement of people and dogs may have begun soon after the domestication of the dog from a gray wolf ancestor in the late Pleistocene. Here, by comparing population genetic results of humans and dogs from Siberia, Beringia, and North America, we show that there is a close correlation in the movement and divergences of their respective lineages. This evidence places constraints on when and where dog domestication took place. Most significantly, it suggests that dogs were domesticated in Siberia by ∼23,000 y ago, possibly while both people and wolves were isolated during the harsh climate of the Last Glacial Maximum. Dogs then accompanied the first people into the Americas and traveled with them as humans rapidly dispersed into the continent beginning ∼15,000 y ago.
The dog was the first domesticated animal but it remains uncertain when the domestication process began and whether it occurred just once or multiple times across the Northern Hemisphere. To ...ascertain the value of modern genetic data to elucidate the origins of dog domestication, we analyzed 49,024 autosomal SNPs in 1,375 dogs (representing 35 breeds) and 19 wolves. After combining our data with previously published data, we contrasted the genetic signatures of 121 breeds with a worldwide archeological assessment of the earliest dog remains. Correlating the earliest archeological dogs with the geographic locations of 14 so-called "ancient" breeds (defined by their genetic differentiation) resulted in a counterintuitive pattern. First none of the ancient breeds derive from regions where the oldest archeological remains have been found. Second, three of the ancient breeds (Basenjis, Dingoes, and New Guinea Singing Dogs) come from regions outside the natural range of Canis lupus (the dog's wild ancestor) and where dogs were introduced more than 10,000 y after domestication. These results demonstrate that the unifying characteristic among all genetically distinct so-called ancient breeds is a lack of recent admixture with other breeds likely facilitated by geographic and cultural isolation. Furthermore, these genetically distinct ancient breeds only appear so because of their relative isolation, suggesting that studies of modern breeds have yet to shed light on dog origins. We conclude by assessing the limitations of past studies and how next-generation sequencing of modern and ancient individuals may unravel the history of dog domestication.
Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology ...to the Americas, but whether the Inuit adopted local Palaeo-Inuit dogs or introduced a new dog population to the region remains unknown. To test these hypotheses, we generated mitochondrial DNA and geometric morphometric data of skull and dental elements from a total of 922 North American Arctic dogs and wolves spanning over 4500 years. Our analyses revealed that dogs from Inuit sites dating from 2000 BP possess morphological and genetic signatures that distinguish them from earlier Palaeo-Inuit dogs, and identified a novel mitochondrial clade in eastern Siberia and Alaska. The genetic legacy of these Inuit dogs survives today in modern Arctic sledge dogs despite phenotypic differences between archaeological and modern Arctic dogs. Together, our data reveal that Inuit dogs derive from a secondary pre-contact migration of dogs distinct from Palaeo-Inuit dogs, and probably aided the Inuit expansion across the North American Arctic beginning around 1000 BP.
The evolutionary history of dogs in the Americas Ní Leathlobhair, Máire; Perri, Angela R; Irving-Pease, Evan K ...
Science (American Association for the Advancement of Science),
2018-Jul-06, 2018-07-06, 20180706, Letnik:
361, Številka:
6397
Journal Article
Recenzirano
Odprti dostop
Dogs were present in the Americas before the arrival of European colonists, but the origin and fate of these precontact dogs are largely unknown. We sequenced 71 mitochondrial and 7 nuclear genomes ...from ancient North American and Siberian dogs from time frames spanning ~9000 years. Our analysis indicates that American dogs were not derived from North American wolves. Instead, American dogs form a monophyletic lineage that likely originated in Siberia and dispersed into the Americas alongside people. After the arrival of Europeans, native American dogs almost completely disappeared, leaving a minimal genetic legacy in modern dog populations. The closest detectable extant lineage to precontact American dogs is the canine transmissible venereal tumor, a contagious cancer clone derived from an individual dog that lived up to 8000 years ago.
The study of fossil parasites can provide insight into the antiquity of host–parasite relationships and the origins and evolution of these paleoparasites. Here, a coprolite (fossilized feces) from ...the 1.2-million-yr-old paleontological site of Haro River Quarry in northwestern Pakistan was analyzed for paleoparasites. Micromorphological thin sectioning and Fourier-transform infrared spectrometry (FTIR) analysis confirms the coprolite belonged to a bone-eating carnivore, likely the extinct giant short-faced hyena (Pachycrocuta brevirostris). Parasitological analysis shows the coprolite to be positive for Toxocara sp. To our knowledge, this is the earliest evidence for Toxocara sp. found.
Shotgun metagenomics applied to archaeological feces (paleofeces) can bring new insights into the composition and functions of human and animal gut microbiota from the past. However, paleofeces often ...undergo physical distortions in archaeological sediments, making their source species difficult to identify on the basis of fecal morphology or microscopic features alone. Here we present a reproducible and scalable pipeline using both host and microbial DNA to infer the host source of fecal material. We apply this pipeline to newly sequenced archaeological specimens and show that we are able to distinguish morphologically similar human and canine paleofeces, as well as non-fecal sediments, from a range of archaeological contexts.
Objectives
We measured carbon and nitrogen isotopic ratios in a contemporary population, and tested how the isotopic variability relates to measures of socioeconomic status (e.g., household wealth) ...and anthropometric measures (e.g., standardized height‐for‐age and weight‐for‐age z‐scores).
Methods
Hair samples from individuals living in the Bosawas Biosphere Reserve in Nicaragua were analyzed for δ13C and δ15N, and these data were examined in relation to individual (e.g., age, sex, anthropometrics) and household (e.g., household size, wealth) variables.
Results
We found through mixed‐effects modeling that δ13C and δ15N varied predictably with individual age and household wealth. δ13C and δ15N did not, however, improve models predicting variation in individual anthropometric measures.
Conclusion
These results indicate that, although there is a relationship between diet (δ13C and δ15N) and socioeconomic variables, these dietary differences are not the main cause of health differences in this population.
Purpose
Dicer, an RNase III type endonuclease, is a key enzyme involved in miRNA biogenesis. It has been shown that this enzyme is essential for several aspects of postnatal kidney functions and ...homeostasis. In this study, we have examined conditional knockout (cKO) mice for Dicer in Pax8 (Paired‐box gene 8) expressing cells to investigate the kidney protein profile. This specific model develops a glomerulocystic phenotype coupled with urinary concentration impairment, proteinuria, and severe renal failure.
Experimental design
Proteomic analysis was performed on kidney tissue extracts from cKO and control (Ctr) mice by 2D Gel Electrophoresis coupled with mass spectrometry.
Results
The analysis highlighted 120 protein spots differentially expressed in Dicer cKO tissue compared with control; some of these proteins were validated by Western blotting. Ingenuity Pathway Analysis led to the identification of some interesting networks; among them, the one having ERK as a central hub may explain, through the modulation of the expression of a number of identified protein targets, the metabolic and structural alterations occurring during kidney cyst development in Dicer cKO mouse model.
Conclusions and clinical relevance
Our results contribute to gain new insights into molecular mechanisms through which Dicer endonuclease controls kidney development and physiological functions.
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