The skeletons of Lucy (left) and Kadanuumuu (right). Both belong to the early human species Australopithecus afarensis. (Images not to scale.)

I never fully appreciated how small Lucy was until I saw her bones for myself. Photographs and restorations of her and her kin within the species Australopithecus afarensis had never really given me a proper sense of scale, and when I looked over her incomplete skeleton – formally known as specimen A.L. 288-1 – I was struck by her diminutive proportions. In life she would have only been about three and a half feet tall. Her physical stature seemed to be inversely proportional to the influence her bones have had on our understanding of our origins.

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