title: Selection for Oil Content During Soybean Domestication Revealed by X-Ray Tomography of Ancient Beans.
abstract: When and under what circumstances domestication related traits evolved in soybean (Glycine max) is not well understood. Seed size has been a focus of archaeological attention because increased soybean seed weight/size is a trait that distinguishes most modern soybeans from their ancestors; however, archaeological seed size analysis has had limited success. Modern domesticated soybean has a significantly higher oil content than its wild counterpart so oil content is potentially a source of new insight into soybean domestication. We investigated soybean oil content using X-ray computed tomography (CT; specifically, synchrotron radiation X-ray CT or SRX-CT) of charred, archaeological soybean seeds. CT identified holes in the specimens that are associated with oil content. A high oil content facilitates the development of small holes, whereas a high protein content results in larger holes. The volume of small holes increased slowly from 7,500 to 4,000 cal B.P. We infer that human selection for higher oil content began as early as 7,500 cal B.P. and that high oil content cultivars were well established by 4,000 cal B.P.
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Yunbing
authors.initials: Y
authors.lastname: Zong
authors.affiliation: School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
authors.forename: Shengkun
authors.initials: S
authors.lastname: Yao
authors.affiliation: Department of Anthropology, University of Toronto Mississauga, Mississauga, Ontario, L5L 1C6, Canada.
authors.forename: Gary W
authors.initials: GW
authors.lastname: Crawford
authors.affiliation: Department of Archaeology, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Fang
authors.affiliation: Department of Archaeology, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Lang
authors.affiliation: School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
authors.forename: Jiadong
authors.initials: J
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Xiulan
authors.initials: X
authors.lastname: Duan
authors.affiliation: Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Guangzhao
authors.initials: G
authors.lastname: Zhou
authors.affiliation: Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
authors.forename: Tiqiao
authors.initials: T
authors.lastname: Xiao
authors.affiliation: Department of Archaeology, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Fengshi
authors.initials: F
authors.lastname: Luan
authors.affiliation: Department of Archaeology, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Archaeology, Shandong University, Jinan, Shandong 250100, China.
authors.forename: Xuexiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan, Shandong 250100, China.|School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China.
authors.forename: Huaidong
authors.initials: H
authors.lastname: Jiang
mesh_terms: D001106:Archaeology; D005075:Biological Evolution; D002681:China; D000071278:Domestication; D013024:Soybean Oil / Q000737:chemistry*; D013025:Glycine max / Q000737:chemistry*; D014056:Tomography, X-Ray
chemical_list: D013024:Soybean Oil