Stride lengths, speed and energy costs in walking of Australopithecus afarensis:Using evolutionary robotics to predict locomotion of early human ancestors

This paper uses techniques from evolutionary robotics to predict the most energy-efficient upright walking gait for the early human relative Australopithecus afarensis, based on the proportions of the 3.2 million year old AL 288-1 ‘Lucy’ skeleton, and matches predictions against the nearly contemporaneous (3.5–3.6 million year old) Laetoli fossil footprint trails. The technique creates gaits de novo and uses genetic algorithm optimization to search for the most efficient patterns of simulated muscular contraction at a variety of speeds. The model was first verified by predicting gaits for living human subjects, and comparing costs, stride lengths and speeds to experimentally determined values for the same subjects. Subsequent simulations for A. afarensis yield estimates of the range of walking speeds from 0.6 to 1.3 m s(−1) at a cost of 7.0 J kg(−1) m(−1) for the lowest speeds, falling to 5.8 J kg(−1) m(−1) at 1.0 m s(−1), and rising to 6.2 J kg(−1) m(−1) at the maximum speed achieved. Speeds previously estimated for the makers of the Laetoli footprint trails (0.56 or 0.64 m s(−1) for Trail 1, 0.72 or 0.75 m s(−1) for Trail 2/3) may have been underestimated, substantially so for Trail 2/3, with true values in excess of 0.7 and 1.0 m s(−1), respectively. The predictions conflict with suggestions that A. afarensis used a ‘shuffling’ gait, indicating rather that the species was a fully competent biped

The Unintended Consequences of Brexit: the Case of Work-Life Balance

Author's chapter from the book Gender and Queer Perspectives on Brexit. This collection examines the opportunities and challenges, rights and wrongs, and prospects and risks of Brexit from the perspectives of gender and sexuality. While much has been written about Brexit from legal, political, social and economic perspectives, there has been little analysis of the effects of Brexit on women and gender/sexual minorities who have historically been marginalised and whose voices have been less audible in political debates – both nationally and at the European level. The collection explores how Brexit might change the equality, human rights and social justice landscape, but from the viewpoint of women and gender/sexual minorities. The contributions gathered in it demonstrate the variety of ways that Brexit will make a difference to the lives of women and individuals marginalised because of gender or sexual identity. </p