An artist uses science, art and imagination to reconstruct the most famous Australopithecus, Lucy.
I have an interesting job. Some days it might involve paying a woman to climb up and down a pole naked while I take notes and photographs.
But that’s a terrible way to begin. Let me explain.
When I first learned of Lucy’s discovery, I wanted to build her. Lucy is the name given to a 3.2-million-year-old partial skeleton attributed to Australopithecus afarensis. It is a wonderful endeavor to seek answers to questions about how she lived, but seeing her as she may have appeared in life can make a connection for us that nothing else can foster.
My first chance to build Lucy’s body came in 1996, when the Denver Museum of Nature and Science (then Natural History) asked me to produce a life-sized, three-dimensional reconstruction, as lifelike as current methods would allow.
If her skeleton was properly articulated, and I used the muscle attachment sites visible on her bones to build her body muscle by muscle, what kind of creature would emerge?
It was obvious from the beginning that the most important issue to represent in the Lucy sculpture was locomotion, including upright walking as well as the issue of whether she climbed trees.
Was there a way to represent both climbing and upright walking in the same pose? It would be tricky, but perhaps I could depict a moment of transition, where it is obvious that Lucy is climbing down from a tree, and equally obvious that she is dropping into an upright position (as opposed to dropping to all fours).
To narrow my search for appropriate poses, I decided to photograph a human climber, preferably a female adult and preferably without clothing, so that I could see how the various muscle groups were being used. The exercise yielded good references for the kind of transitional pose I was looking for.
To create a foot skeleton for Lucy, I essentially executed a 3-D version of a graphic reconstruction done earlier by Berkeley paleoanthropologist Tim White and the University of Tokyo’s Gen Suwa, scaled to Lucy’s size using her preserved foot bones.
This involved casting a number of foot bones known for A. afarensis, including a partial foot skeleton, in a shrinkable material, and shrinking them to Lucy’s size. I then built tendons and musculature and, eventually, skin.
The resulting foot was weird-looking by modern human standards. Even with the big toe adducted into line with the others, the long lateral toes give a hint of the hand-like look of the feet of nonhuman primates.
The head reconstructed for the Lucy figure was based on a composite female skull restoration. The reconstruction of a more complete male skull, A.L. 444-2, at left, is a more typical case study.
The sites where the chewing muscles were attached to the skull are very strongly marked in the A.L. 444-2 skull, indicating well-developed muscles. The lower nasal bones are flat and show no indications of a projecting nose. Any reasonable reconstruction of nasal cartilages results in a flat, apelike nose.
Many of the distinctive features of the restored A.L. 444-2 skull are reflected in the final form of the fleshed-out head. The lateral flare of the cheekbones results in a very wide face. The jaws project forward, with a convex area between the nose and mouth.
The head reconstructed for the Lucy figure, based on the composite female skull restoration, proceeded similarly, and looks much like a daintier version of the A.L. 444-2 reconstruction.
Lucy’s skeleton displays many clues about the position and development of her musculature in life. These can be “read” using the anatomy of modern apes and humans as guides for their interpretation.
Following the muscle markings on Lucy’s bones, I gave her arms that are well muscled—not bulky like a bodybuilder’s arms, but more like those of a very athletic dancer. When fleshed out, her arms have a somewhat human look, but with proportionally longer forearms and some apelike nuances in the arrangement of muscles.
The look of her legs is also somewhat human, but her leg muscles are packed onto leg bones that are relatively shorter than ours, and with a stronger (hyperhuman!) angle at the knee.
Lucy was cast in silicone, colored so that she would have dark skin like tropical humans.
The amount of body hair in australopiths is unknown. We assume that the common ancestor of chimps and humans, like all of the non-human apes, had a full coat. We can guess that this coat was lost by the time of Homo erectus, as its skeleton’s proportions show that it was adapting to heat stress like modern humans do, and part of our adaptation involves an enhanced sweat gland cooling system which would not function well with a full coat of body hair.
For Lucy, I chose a model that was at the sparsest end of the range for living chimpanzees. Because its taper, color, and straightness make black bear hair a good stand-in for chimp or gorilla fur, this is what I used for Lucy.
About a million individual hairs were punched into Lucy’s silicone skin over a period of three months (in each of her incarnations, for the Denver museum and later for the Smithsonian).
As Lucy’s body took shape under my fingers, it became evident that it would not be like that of any creature alive today. There are both apelike and familiarly humanlike aspects of her anatomy, but her body is not identical to either.
The implication of the anatomical work is that, when reconstructing Lucy, she must be met on her own terms. I could not build a diminutive human form over this unique skeleton, nor could I build that of an ape. The process reveals a body unique to her kind.
All text excerpted from Shaping Humanity by John Gurche. Published by Yale University Press in November 2013.
Text and images copyright John Gurche / courtesy Yale University Press. Reproduced by permission.
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