Data from: New World cattle show ancestry from multiple independent domestication events

Previous archeological and genetic research has shown that modern cattle breeds are descended from multiple independent domestication events of the wild aurochs (Bos primigenius) about ten thousand years ago. Two primary areas of domestication in the Middle East/Europe and the Indian subcontinent resulted in taurine and indicine lines of cattle, respectively. American descendants of cattle brought by European explorers to the New World beginning in 1493 generally have been considered to belong to the taurine lineage. Our analyses of 54,609 single nucleotide polymorphisms show that these New World cattle breeds, as well as the many related breeds of cattle in southern Europe, actually exhibit ancestry from both the taurine and indicine lineages. In this study we show that although European cattle are largely descended from the taurine lineage, gene flow from the indicine lineage has contributed substantial genomic components to both southern European cattle breeds and their New World descendants. New World cattle breeds, such as Texas Longhorns, provide an opportunity to study global population structure and domestication in cattle. Following their introduction into the Americas in the late 1400s, semi-feral herds of cattle underwent between 80 and 200 generations of predominantly natural selection, as opposed to the human-mediated artificial selection of Old World breeding programs. Our analyses of global cattle breed population history show that the hybrid ancestry of New World breeds contributed genetic variation that likely facilitated the adaptation of these breeds to a novel environment.

既往考古学与遗传学研究表明，现代家牛品种约于一万年前由野生原牛（Bos primigenius）的多次独立驯化事件演化而来。家牛驯化的两大核心区域分别位于中东/欧洲与印度次大陆，由此分别孕育了普通牛（taurine）与瘤牛（indicine）两大谱系。学界普遍认为，1493年起由欧洲探险家带入新大陆的家牛及其美洲后代均属于普通牛谱系。我们对54609个单核苷酸多态性（single nucleotide polymorphisms, SNP）位点的分析显示，这些新大陆家牛品种以及南欧诸多近缘家牛品种，实际上同时携带两大谱系的血统。本研究证实，尽管欧洲家牛大体上源自普通牛谱系，但瘤牛谱系的基因流（gene flow）为南欧家牛品种及其美洲后代均贡献了大量的基因组组分。诸如德克萨斯长角牛（Texas Longhorns）这类新大陆家牛品种，为研究家牛的全球种群结构与驯化历程提供了绝佳契机。自15世纪末被引入美洲后，半野生的家牛群经历了80至200代的以自然选择为主导的演化过程，而非旧大陆育种计划中人类主导的人工选择。我们对全球家牛品种种群历史的分析显示，新大陆家牛品种的杂交血统所带来的遗传变异，或助力这些品种快速适应全新的生存环境。