though chickens (Gallus gallus domesticus) are globally ubiquitous today, the timing, location, and manner of their domestication is contentious. Until recently, archaeologists placed the origin of the domestic chicken in northern China, perhaps as early as 8,000 years ago. Such evidence however complicates our understanding of how the chicken was domesticated because its wild progenitor-the red jungle fowl (Gallus gallus)-lives in tropical ecosystems and does not exist in northern china today or in the recent past. increasingly, multiple lines of evidence suggest that many of the archaeological bird remains underlying this northern origins hypothesis have been misidentified. Here we analyze the mitochondrial DnA of some of the earliest purported chickens from the Dadiwan site in northern china and conclude that they are pheasants (Phasianus colchicus). curiously, stable isotope values from the same birds reveal that their diet was heavy in agricultural products (namely millet), meaning that they lived adjacent to or among some of the earliest farming communities in east Asia. We suggest that the exploitation of these baited birds was an important adaptation for early farmers in china's arid north, and that management practices like these likely played a role in the domestication of animalsincluding the chicken-in similar contexts throughout the region. Northern China is one of the few places where agriculture evolved independently ca. 9,000-7,000 calibrated years before the present (cal BP) and with a suite of plant and animal domesticates unique to the region, namely Panicum and Setaria millets, pigs, dogs, and a medium-size bird most typically identified as chicken 1,2. The causes of this agricultural revolution are the subject of much debate 3-5 , as is the direct evidence for it 6. Among the most contentious of these is the role of the chicken (Gallus gallus domesticus) in the agricultural origins of East Asia 7-10. Indeed, there is no scientific consensus on where, when, or how the domestic chicken evolved, despite the fact that chickens are the most ubiquitous domestic animal on earth today 11. Chinese archaeological contexts that contain other evidence for agricultural life, often contain bones of medium-sized birds identified as "chicken," the oldest of which have been touted as the epicenter of chicken domestication. This is problematic because some of the oldest locations are in the arid regions of northern China where the wild ancestor of the domestic chicken-the tropically adapted "red jungle fowl" (Gallus gallus)-does not thrive today 12. Here we present evidence that the birds exploited by the some of the earliest agricultural peoples of arid northwest China were not chickens at all, but rather pheasants (Phasianus spp.), and closely related to the wild pheasants that today thrive in the arid environments of northern Eurasia. Importantly, as with other domestic and commensal animals throughout China and around the world, these birds were dependent upon an environment of resources that exists only i...

The earliest Native Americans have often been portrayed as either megafaunal specialists or generalist foragers, but this debate cannot be resolved by studying the faunal record alone. Stable isotope analysis directly reveals the foods consumed by individuals. We present multi-tissue isotope analyses of two Ancient Beringian infants from the Upward Sun River site (USR), Alaska (~11,500 years ago). Models of fetal bone turnover combined with seasonally-sensitive taxa show that the carbon and nitrogen isotope composition of USR infant bone collagen reflects maternal diets over the summer. Using comparative faunal isotope data, we demonstrate that although terrestrial sources dominated maternal diets, salmon was also important, supported by carbon isotope analysis of essential amino acids and bone bioapatite. Tooth enamel samples indicate increased salmon use between spring and summer. Our results do not support either strictly megafaunal specialists or generalized foragers but indicate that Ancient Beringian diets were complex and seasonally structured.

PCR inhibitors are a formidable problem to the study of aged, degraded, and/or low copy number DNA. As a result, there is a need to find alternate methods that ameliorate the efficacy of PCR. In this study, we attempted to use genetic methods to identify the species of salmonid (Oncorhynchus spp.) remains recovered from archaeological sites along the Feather River located in northern California, United States. In the process of doing so, we compared the efficacy of a PCR enhancer cocktail called "PEC-P" and a reagent rich PCR recipe called "rescue PCR" over standard PCR. Across all treatments (full concentration and 1:10 dilute eluates subjected to standard PCR, PEC-P, and rescue PCR) species identification was possible for 74 of 93 archaeological fish specimens (79.6%). Overall, six of the 93 samples (6.5%) consistently yielded species identification across all treatments. The species of ten specimens (10.8%) were uniquely identified from amplicons produced with either PEC-P or rescue PCR or both. Notably, the species of seven samples (7.5%) were uniquely identified with standard PCR over the alternative treatments. Considering both full concentration and 1:10 dilute eluates (N = 186), standard PCR performed as well as PEC-P (p = 0.1451) and rescue (p = 0.6753). Yet, considering results from full concentration eluates alone (N = 93), PEC-P (60.2%) outperformed both standard PCR (44.1%; p = 0.0277) and rescue PCR (40.9%; p = 0.0046). Stochasticity observed in our study cautions us against choosing a "best" performing method of those explored here and suggests their respective potentials to improve success may be sample dependent. When working with samples compromised by PCR inhibitors, it is useful to have alternative methodologies for subduing the problem. Both PEC-P and rescue PCR represent useful alternative methods for the study of aged, degraded, and/or low copy number DNA samples compromised by PCR inhibitors.

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