Subscribe free to our newsletters via your
. Earth Science News .




Subscribe free to our newsletters via your




















ABOUT US
UT study cracks coldest case: How the most famous human ancestor died
by Staff Writers
Austin TX (SPX) Aug 31, 2016


UT Austin professors John Kappelman and Richard Ketcham examine casts of Lucy while scanning the original fossil (background). Image courtesy Marsha Miller. For a larger version of this image please go here.

Lucy, the most famous fossil of a human ancestor, probably died after falling from a tree, according to a study appearing in Nature led by researchers at The University of Texas at Austin.

Lucy, a 3.18-million-year-old specimen of Australopithecus afarensis - or "southern ape of Afar" - is among the oldest, most complete skeletons of any adult, erect-walking human ancestor. Since her discovery in the Afar region of Ethiopia in 1974 by Arizona State University anthropologist Donald Johanson and graduate student Tom Gray, Lucy - a terrestrial biped - has been at the center of a vigorous debate about whether this ancient species also spent time in the trees.

"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 studied 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. For 10 days, Kappelman and geological sciences professor Richard Ketcham carefully scanned all of her 40-percent-complete skeleton to create a digital archive of more than 35,000 CT slices.

"Lucy is precious. There's only one Lucy, and you want to study her as much as possible," Ketcham said. "CT is nondestructive. So you can see what is inside, the internal details and arrangement of the internal bones."

Studying Lucy and her scans, Kappelman noticed something unusual: The end of the right humerus was fractured in a manner not normally seen in fossils, preserving a series of sharp, clean breaks with tiny bone fragments and slivers still in place.

"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," said Kappelman, who 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 injury was 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.

Kappelman observed similar but less severe fractures at the left shoulder and other compressive fractures throughout Lucy's skeleton including 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 question remained: How could Lucy have achieved the height necessary to produce such a high velocity fall and forceful impact? Kappelman argued that because of her small size - about 3 feet 6 inches and 60 pounds - Lucy probably foraged and sought nightly refuge in trees.

In comparing her with chimpanzees, Kappelman suggested Lucy probably fell from a height of more than 40 feet, hitting the ground at more than 35 miles per hour. Based on the pattern of breaks, Kappelman hypothesized that she landed feet-first before bracing herself with her arms when falling forward, and "death followed swiftly."

"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."

Kappelman conjectured that because Lucy was both terrestrial and arboreal, features that permitted her to move efficiently on the ground may have compromised her ability to climb trees, predisposing her species to more frequent falls. Using fracture patterns when present, future research may tell a more complete story of how ancient species lived and died.

In addition to the study, the Ethiopian National Museum provided 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."

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

.


Related Links
University of Texas at Austin
All About Human Beings and How We Got To Be Here






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Previous Report
ABOUT US
Smarter brains are blood-thirsty brains
Adelaide, Australia (SPX) Sep 01, 2016
A University of Adelaide-led project has overturned the theory that the evolution of human intelligence was simply related to the size of the brain - but rather linked more closely to the supply of blood to the brain. The international collaboration between Australia and South Africa showed that the human brain evolved to become not only larger, but more energetically costly and blood thirsty th ... read more


ABOUT US
Germany to rebuild Italy school, quake grift probe deepens

Drawing out children's trauma in quake-hit Italy

Myanmar's Suu Kyi faces test at ethnic peace conference

Obama defends Louisiana flood response

ABOUT US
UNIST to engineer next-generation smart separator membranes

3-D-printed structures 'remember' their shapes

Berlin's IFA fair dons virtual reality headsets

New method developed for producing some metals

ABOUT US
U.S. funding tidal energy research programs

Torrential monsoon rains bring Indian capital to halt

University of Akron researchers find thin layers of water can become ice-like at room temperature

Vegetation matters

ABOUT US
Technique could assess historic changes to Antarctic sea ice and glaciers

A mammoth undertaking

By mid-century, more Antarctic snowfall may help offset sea-level rise

Giant cruise ship heads to Arctic on pioneering journey

ABOUT US
Plants found to regulate leaf temperature to boost carbon uptake

Making pesticide droplets less bouncy could cut agricultural runoff

Plants' future water use affects long-term drought estimates

More tomatoes, faster: Accelerating tomato engineering

ABOUT US
17 unaccounted for in typhoon-hit northern Japan

Tsunami but no damage after powerful 7.1 quake jolts New Zealand

Hurricane Madeline weakening as it heads toward Hawaii

Japan typhoon kills nine in elderly home

ABOUT US
Corruption 'epidemic' in Tunisia: anti-graft chief

S.Sudan court martials 60 soldiers

Conflict and drought threaten Mozambique's Gorongosa park

Boko Haram's Shekau 'wounded' in air strike: Nigeria

ABOUT US
UT study cracks coldest case: How the most famous human ancestor died

Smarter brains are blood-thirsty brains

Study: Math-capable parents yield math-capable kids

Scientists think human ancestor Lucy fell from a tree




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement