The challenge at the dry wash full of pebbles and cobbles and boulders was to spot the four “obvious” (to a trained fossil hunter!) fossils that lay exposed amid the geologic rubble. I spotted one of the four bone fragments immediately, and wondered if that was the magical bone that had caught Johanson’s eye, too. After some study, I decided I could see two more, but the fourth eluded me until I hit the “I give up!” button and spotlights hit all four specimens. None of the visitors around me managed to spot more than three, either.
At another station, a human (or hominid -- they are so similar!) skeleton had been drawn on a table, and the challenge was to place jumbled bones (casts, of course) in the right spots. Yet other matching games involved trying to figure out which complete bones were represented by fossilized fragments.
Lucy, although fully grown, was about the size of a contemporary six-year-old girl. Several of the exhibits compared her features to a chimpanzee’s and a human’s, to show how she fit into the winding, wobbly, rather dotted evolutionary line that connects us.
At one station, three skulls -- chimp, Lucy, and human -- were attached via their foramens magnum (the hole in the base through which the spinal cord passes) to the tops of what looked like two-liter plastic soda bottles. The bottles were filled with blue water, marked with lines showing cubic centimeters (cc), and mounted so that they could be turned upside down. When you flipped one over, the skull hung down and blue water poured into the brain case, and you could see by the bottle’s marks how many cc’s it took to fill the brain case. The chimpanzee and Lucy were remarkably close, about 400 ccs each, while the human skull’s brain volume was around 1250 ccs. Up until Lucy’s discovery and analysis, scientists believed that brain volume had increased before walking upright -- bipedalism -- took root. This was one of the major theories of human origin that Lucy’s remains shifted.
Another station invited you to examine the pelvises of a female chimp, Lucy, and a female human. They were mounted to the wall, but on a ball-joint, so that you could really move them around and look at them from different angles. The signs pointed out differences between the chimp and Lucy (and similarities between her and the human) that made it clear that she was bipedal. They also pointed out birth canal similarities the between the chimp and Lucy (and differences between her and the human) that indicated that her offspring would indeed be small-brained as compared to a human.
Still other stations explored the differences and similarities among the knee joints, teeth, and posture of the three species.
From the interactive exhibit room, a long ramp led up to Lucy’s chamber. Every fifteen feet or so, the skull of one of our hominid ancestors stood on a pedestal: Ardipithecus ramidus, Australopithecus afarensis (Lucy’s species), Australopithecus robustus, Homo erectus, Homo habilis, Neanderthal man, and finally Homo sapiens. They were just beautiful, and I kept going back and forth, comparing and contrasting. Just before the entry to Lucy’s room was a five-minute video interview of Johanson, and I made myself sit through it before I let myself go into the final darkened chamber, where Lucy herself lay.
The room was circular, and all around was a mural showing fleshed-out hominids in their probable environments. They carried babies, peered from behind bushes, snatched big flying insects out of the sky -- one even seemed to be wrestling a crocodile, which I found a bit jarring. From the explanatory text, I gathered that the latest thinking is that bipedalism began not in the grasslands, where it might give the advantage of seeing over the tall grass, but rather in the forest, where it granted better mobility.
To the right of the entry stood a glass case showing casts of Lucy’s bones put together as though she was standing upright. A mirror at the back of the case let you compare your body to her gracile and incomplete skeleton. The audio presentation for that display talked about how amazing it was that nearly forty percent of her skeleton was recovered, and how even more fortunate that there was enough to “mirror” her left and right sides’ missing pieces: how her lower right leg bone could be used to create a mirror image to take the place of the missing left lower leg bone, while the left upper could be used to complete the right, and so on.
On the other side of the room another upright case surrounded an “artist’s reconstruction” of a fleshed-out Lucy. Diminutive and sporting thumb-like big toes (her feet looked closer to chimps than humans -- they only ever found two toe bones), she was depicted covered with sparse but coarse hair, short and reddish-brown. The hair covered her entire body except for her face, chest, stomach, and the palms of her hands. Her exposed dark skin had the shiny, leathery look of a chimp’s, and her soulful brown eyes were surrounded by crinkles, which made me think she must have smiled a lot.
Finally I let myself approach the glass-shrouded table in the center of the room, where Lucy’s bones -- the actual fossils recovered from that hot and dusty gully in Ethiopia a lifetime ago -- were laid out in their familiar resting conformation. There are only about 30 bones, represented in whole or in part(s), and it was fascinating to see the hairline cracks where they hundreds of pieces had been fitted together to make them. In the short video introduction Johanson had said that most of those pieces had been partially encased in sandstone matrix, all of which had to be carefully removed before they even knew the true shape of each little fragment.
I couldn’t believe my good fortune to be standing there gazing upon Lucy’s actual bones. I went back and forth between the displays in her chamber, comparing every inch of bone to the fleshed-out mannequin, then backtracked down the ramp to look again at each ancestral skull, and then returned to Lucy’s chamber to marvel at her all over again. All told I spent three hours in the exhibit, and only left when I realized I was in danger of missing the IMAX film I had a ticket for!
The article that alerted me to Lucy’s presence in Seattle went on to say that other museums that had been planning to show Lucy’s Legacy were backing out of the deal in droves, afraid they, like the Seattle museum, would lose money on the show, which is very expensive to host. It’s a shame, and a wonder to me, that Lucy didn’t have a better showing. It will be a loss to us all if she has to go back to her vault in Ethiopia before her five-year planned tour of the US expires.
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