The earliest farmers of northwest China exploited grain-fed pheasants not chickens

Published: 13 February 2020

Loukas Barton, Brittany Bingham, Krithivasan Sankaranarayanan, Cara Monroe, Ariane Thomas & Brian M. Kemp

Abstract
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 animals – including the chicken – in similar contexts throughout the region.

Introduction
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 chicken1,2. The causes of this agricultural revolution are the subject of much debate3,4,5, as is the direct evidence for it6. Among the most contentious of these is the role of the chicken (Gallus gallus domesticus) in the agricultural origins of East Asia7,8,9,10. 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 today11.

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 today12. 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 in an agricultural ecosystem managed and perpetuated by humans.

Study Specimens
The present study is an extension of a broader effort to understand the origins of agriculture and the co-evolution of domestic plants, animals, and people in arid East Asia2,3,13,14. Specimens analyzed here were first collected during the 1978-1984 excavations15 of the Dadiwan Neolithic site in Gansu Province, PRC (Fig. 1). Though human hunter-gatherers visited the Dadiwan site sporadically over the past 80,000 years16, the earliest evidence for agricultural behavior (i.e., storage features, domestic structures, carbonized remains of cereals, and isotopic evidence that the local dogs had been foddered with those cereals year-round) does not appear until ~7,800 cal BP, during the Laoguantai cultural period2. By 6,300 cal BP (the Yangshao cultural period), Neolithic life at Dadiwan was intensively agricultural and culturally complex, with densely packed communities marked by permanent architecture, storage facilities, craft production zones, lavish burials, two kinds of morphologically domestic millets, and isotopic evidence that both dogs, and pigs (in abundance) were provisioned throughout the year with stored grain2.

More:
https://www.nature.com/articles/s41598-020-59316-5