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Scatterplots with LOWESS lines illustrating temporal variation in body mass in Southern, Central and Northern Europe, the Nile Valley, South Asia, and China. Lowess smoothing parameter: Southern Europe = 0.9, Central Europe = 0.8, Northern Europe = 0.9, Nile Valley = 1.1, South Asia = 1.1, China = 1.0. Shaded regions represent 95% confidence intervals around fit lines.
