Lucy (AL 288) - Australopithecus Skeleton from Ethiopia

Lucy (AL 288) - Australopithecus Skeleton from Ethiopia Lucy is the name of the nearly complete skeleton of an Australopithecus afarensis. She was the first nearly complete skeleton recovered for the species, found in 1974 at the Afar Locality (AL) 228, a site in the Hadar archaeological region on the Afar Triangle of Ethiopia. Lucy is about 3.18 million years old, and is called Denkenesh in Amharic, the language of the local people. Lucy is not the only early example of A. afarensis found at Hadar: many more A. afarensis hominids were found at the site and the nearby AL-333. To date, over 400 A. afarensis skeletons or partial skeletons have been found in the Hadar region from about a half-dozen sites. Two hundred sixteen of them were found at AL 333; together with Al-288 are referred to as the First Family, and they all date between 3.7 and 3.0 million years ago. What Scientists Have Learned About Lucy and Her Family The numbers of available specimens of A. afarensis from Hadar (including over 30 crania) have allowed continuing scholarship in several regions concerning Lucy and her family. These issues have included terrestrial bipedal locomotion; the expression of sexual dimorphism and how body size shapes human behavior; and the paleoenvironment in which A. afarensis lived and thrived. Lucys post-cranium skeleton expresses multiple features related to habitual striding bipedalism, including elements of Lucys spine, legs, knees, feet, and pelvis. Recent research has shown that she didnt move in ​the  same way as humans do, nor was she simply a terrestrial being. ​A. afarensis may well have still been adapted to live and work in trees at least part time. Some recent research (see Chene et al) also suggests the shape of the females pelves were closer to modern humans and less similar to the great apes.d less similar to the great apes. A. afarensis lived in the same region for over 700,000 years, and during that time, the climate changed several times, from arid to moist, from open spaces to closed forests and back again. Yet, A. afarensis persisted, adapting to those changes without requiring major physical changes. Sexual Dimorphism Debate Significant sexual dimorphismthat female animal bodies and teeth are significantly smaller than malesis typically found in species which have intense male to male competition. A. afarensis possesses a degree of postcranial skeletal size dimorphism matched or exceeded only by the great apes, including orangutans and gorillas. However, A. afarensis teeth are not significantly different between males and females. Modern humans, by comparison, have low levels of male-male competition, and male and female teeth and body size are far more similar. The peculiarity of that is stil debated: teeth size reduction may be the result of adapting to a different diet, rather than a signal of less male-to-male physical aggression. Lucys History The central Afar basin was first surveyed by Maurice Taieb in the 1960s; and in 1973, Taieb, Donald Johanson and Yves Coppens formed the International Afar Research Expedition to begin extensive exploration of the region. Partial hominin fossils were discovered in Afar in 1973, and the nearly complete Lucy was discovered in 1974. AL 333 was discovered in 1975. Laetoli was discovered in the 1930s, and the famous footprints discovered in 1978. Various dating measures have been used on the Hadar fossils, including Potassium/Argon (K/AR) and geochemical analysis of the volcanic tuffs, and currently  , scholars have tightened the range to between 3.7 and 3.0 million years ago. The species was defined, using Hadar and A. afarensis specimens from Laetoli in Tanzania, in 1978. Lucys Significance Lucy and her familys discovery and investigation remodeled physical anthropology, making it a much more rich and nuanced field than before, partly because the science changed, but also because for the first time, scientists had an adequate database to investigate all the issues around her. In addition, and this is a personal note, I think one of the most significant things about Lucy is that Donald Johanson and Edey Maitland wrote and published a popular science book about her. The book called Lucy, the Beginnings of Humankind made the scientific chase for the human ancestors accessible to the public.   Sources This article is a part of the About.com guide to the Lower Paleolithic, and the Dictionary of Archaeology. Thanks are owed to Tadewos Assebework, of Indiana University, for correcting some minor errors. Chene G, Lamblin G, Lebail-Carval K, Chabert P, Marà ¨s P, Coppens Y, and Mellier G. 2015. The genital prolapse of Australopithecus Lucy? International Urogynecology Journal 26(7):975-980.Chene G, Tardieu AS, Trombert B, Amouzougan A, Lamblin G, Mellier G, and Coppens Y. 2014. A species’ Odyssey: evolution of obstetrical mechanics from Australopithecus Lucy to nowadays. European Journal of Obstetrics Gynecology and Reproductive Biology 181:316-320.DeSilva JM, and Throckmorton ZJ. 2011. Lucys Flat Feet: The Relationship between the Ankle and Rearfoot Arching in Early Hominins. PLoS ONE 5(12):e14432.Johanson DC. 2004. Lucy, Thirty Years Later: An expanded view of Australopithecus afarensis. Journal of Anthropological Research 60(4):465-486.Johanson DC, and White TD. 1979. A systematic assessment of early African hominids. Science 203(4378):321-330.Kimbel WH, and Delezene LK. 2009. â€Å"Lucy† redux: A review of research on Australopithecus afarensis. American Journal of Physical Anthropology 140(S49):2-48. Meyer MR, Williams SA, Smith MP, and Sawyer GJ. 2015. Lucys back: Reassessment of fossils associated with the A.L. 288-1 vertebral column. Journal of Human Evolution 85:174-180.Nagano A, Umberger BR, Marzke MW, and Gerritsen KGM. 2005. Neuromusculoskeletal computer modeling and simulation of upright, straight-legged, bipedal locomotion of Australopithecus afarensis (A.L. 288-1). American Journal of Physical Anthropology 126(1):2-13.Sellers WI, Cain GM, Wang W, and Crompton RH. 2005. Stride lengths, speed and energy costs in walking of Australopithecus afarensis: using evolutionary robotics to predict locomotion of early human ancestors. Journal of The Royal Society Interface 2(5):431-441.