Texas-Led Research Into Death Of World's Most Famous Human Ancestor In Dispute [UPDATED]

AUSTIN, TX -- Reports on the manner of death for Lucy -- the world's most celebrated fossil of a human ancestor-- may be highly exaggerated.

As Patch previously reported (see story below), research led by a University of Texas at Austin concluded that Lucy likely died after falling from a tree. The 3.2-million-year-old specimen of Australopithecus afarensis -- that's Lucy -- is among the oldest, most complete skeletons of any adult, erect-walking ancestor.

In a widely covered bit of news this week, John Kappelman, a UT Austin anthropology and geological sciences professor, averred the mystery of how Lucy died so many millions of years ago had been solved. Citing extensive X-ray analysis, the placement of fractures and the unique nature of those breaks (especially on the humerus bone), Lucy likely fell from a tree from 40 feet -- the fall exacerbated further when she probably put her arms out in a futile attempt to slow her descent.

The findings were published in the journal Nature and everything.

“This compressive fracture results when the hand hits the ground during a fall, impacting the elements of the shoulder against one another to create a unique signature on the humerus,” Kappelman said.

Lucy's efforts were in vain. But that's obvious, since she is a fossil.

But the man who discovered Lucy in the first place disputes the findings. He made that clear to the New York Times in an interview for his reaction to Lucy's prehistoric post-mortem.

"Elephant bones and hippo ribs appear to have the same kind of breakage," Donald Johanson, the eminent paleontologist who discovered Lucy's fossilized bones in Ethiopia in 1974, told the Times. "It's unlikely they fell out of a tree."

Oh yes, he went there. This could be the start of a grudge match, with Johanson's dis of the UT researchers' work the paleontology world's version of real trash talk.

Others are piling on, decidedly on Team Johanson. Ericka N. L’Abbé, a professor of anthropology at the University of Pretoria in South Africa, explained to the Times that when living bones break, some parts bend and a closer inspection of Lucy’s bones might have revealed traces of that bending.

“The major drawback is that they didn’t look under a microscope,” Dr. L’Abbé told the Times.

Pow. This is no debate, but a street fight.

Johanson goes further, disputing the UT researcher's assertions that Lucy spent equal time on the ground as on treetops. By the time of Lucy came along, human ancestors were not really tree-dwelling, having evolved to the point where they searched for food on the ground -- with attendant limbs and feet suitably developed more for that purpose than for climbing trees.

“Australopithecus afarensis was essentially a terrestrial animal,” Johanson told the Times, his words dripping with palpable contempt for the UT findings while decimating that whole falling-out-of-a-tree thing.

Ouch. That's gonna leave a mark.

The New York Times takes its own swipes at the Texas-rooted research.

"Monkeys and apes spend a lot of time in trees and have impressive adaptations for that sort of life," they say (probably inadvertently sounding snobbish, like we couldn't figure out those monkey/ape adaptations on our own). "One of the most striking features of Lucy’s skeleton is the shape of her leg and knee bones, which look suited for walking on the ground instead," the Times scribe adds.

Pow. But wait, there's more.

"Since the discovery of Lucy, paleoanthropologists have found more fossils from Australopithecus afarensis, the Times reporter adds in the piece. "They suggest Lucy had flat feet and other traits needed for walking."

Okay, now it's getting out of hand. Them's fighting words.

The bottom line is the mystery behind the death of Lucy 3.2 million years ago may not have been solved after all. Still, the UT findings make for an interesting read, published in the journal Nature accessed by clicking here.

And either way -- however she made have met her fate -- we love Lucy.

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From Aug. 29:

AUSTIN, TX — As cold cases go, this one is arguably the coldest. University of Texas at Austin researchers have determined how Lucy — the most famous human ancestor fossil — likely died, unveiling their findings on Monday.

Lucy is a 3.18-million-year-old specimen of Australopithecus afarensis and is among the oldest, most complete skeletons of any adult, erect-walking ancestor. Since being discovered in 1974, the most famous terrestrial biped has been at the center of intrigue, with scientists worldwide wondering if this ancient species also spent time in trees.

According to UT-Austin researchers, that may have been the case. Lucy, they say, likely died after falling from a tree.

“It is ironic that the fossil at the center of a debate about the role of arborealism in human evolution likely died from injuries suffered from a fall out of a tree,” said lead author John Kappelman, a UT Austin anthropology and geological sciences professor.

Kappelman first began studying Lucy during her U.S. museum tour in 2008, when the fossil detoured to the High-Resolution X-ray Computed Tomography Facility (UTCT) in the UT Jackson School of Geosciences — a machine designed to scan through materials as solid as a rock and at a higher resolution than medical CT, officials said. Kappelman and geological sciences professor Richard Ketcham spent 10 days, scanning all of her 40-percent-complete skeleton to create a digital archive of more than 35,000 CT slices.

After spending so much time with Lucy, an affection results. Hence Ketcham's comments about the findings related to her death — equal parts science and human affection. “Lucy is precious," Ketcham said. "There’s only one Lucy, and you want to study her as much as possible. CT is nondestructive. So you can see what is inside, the internal details and arrangement of the internal bones.”

While studying the scans, Kappelman came across something odd, he explained. The end of the right humerus was fractured in a way that is not normally seen in fossils. As a result, a series of sharp, clean breaks with tiny bone fragments and slivers was preserved in place, he explained.

“This compressive fracture results when the hand hits the ground during a fall, impacting the elements of the shoulder against one another to create a unique signature on the humerus,” Kappelman said.

Kappelmen didn't rest on his own laurels in coming to the conclusion. He consulted Dr. Stephen Pearce, an orthopedic surgeon at Austin Bone and Joint Clinic, using a modern human-scale, 3-D printed model of Lucy.

Pearce confirmed the post-mortem ruling. The injury was found to be consistent with a four-part proximal humerus fracture, caused by a fall from considerable height when the conscious victim stretched out an arm in an attempt to break the fall, he explained.

Kappelman also found other similar, yet less severe fractures, in other parts of Lucy: on the left shoulder, for one, a pilon fracture of the right ankle, a fractured left knee and pelvis, and even more subtle evidence such as a fractured first rib — “a hallmark of severe trauma” — all consistent with fractures caused by a fall. Without any evidence of healing, Kappelman concluded the breaks occurred perimortem, or near the time of death.

The list of injuries leading to Lucy's death yielded further clues about her life in addition to the manner of her death.

Because of her small size — just 3 feet, 6 inches tall with a weight of 60 pounds — Lucy probably foraged, while seeking nightly refuge in trees, Kappelman concluded. Comparing her behavior to that of a chimpanzee's, Kappelman further suggested Lucy probably fell from a height of more than 40 feet, hitting the ground at 35 miles per hour. Judging from the nature of the injuries, she likely landed feet-first before bracing herself with her arms upon falling forward.

"Death followed swiftly," Kappelman said.

“When the extent of Lucy’s multiple injuries first came into focus, her image popped into my mind’s eye, and I felt a jump of empathy across time and space,” Kappelman said. “Lucy was no longer simply a box of bones but in death became a real individual: a small, broken body lying helpless at the bottom of a tree.”

Lucy's death yields further clues about her species in general.

Kappelman reasons that because Lucy was both terrestrial and tree-dwelling, features that permitted her to move efficiently on the ground may have compromised her ability to climb trees. Apparently, this predisposed her species to more frequent falls.

The findings on Lucy have future big implications. Using fracture patterns when present, future research may tell a more complete story of how ancient species in general lived and died, university officials said.

Researchers solving the mystery of Lucys' death thanked the Ethiopian National Museum for providing access to a set of 3-D files of Lucy’s shoulder and knee for the public to download and print so that they can evaluate the hypothesis for themselves.

“This is the first time 3-D files have been released for any Ethiopian fossil hominin, and the Ethiopian officials are to be commended,” Kappelman said. “Lucy is leading the charge for the open sharing of digital data.”

Those 3-D files, along with other scholastic materials, are available at eLucy.org.

At that website, university officials even provide student activities ideal for educators — including printer-friendly, life-sized renderings of the ancient skeleton, a nine-piece puzzle, bookmarks and a fun word search. One also finds a set of those hard-to-find fossil hominin flash cards you've long wanted to get your hands on.

Permissions to scan, study and photograph Lucy were granted by the Authority for Research and Conservation of Cultural Heritage and the National Museum of Ethiopia of the Ministry of Tourism and Culture, officials said. And UTCT was supported by three grants from the U.S. National Science Foundation.

So the mystery of Lucy's death appears to be solved. She fell from a tree. Or was she pushed? This we might never know, a whodunit lost to the mists of time. But we know now that she probably fell, tumbling to her death.

Yet in many ways, she lives on as she continues to educate us about the past and ourselves. And so, Lucy is a bipedal humanoid for the ages, a citizen of the world. Long live Lucy.

>>> Image: Reconstruction of "Lucy," Warsaw Museum of Evolution, via WikiMedia Commons