Humans, Meet Ardi

(Thumbnail image: mydailyglobalnews.com)

“The biggest find? The fossil bones of a female creature that scientists call Ardi. She stood four feet tall, upright on two feet, weighed 110 pounds, and she drastically changes ideas about human origins.” (NBC Nightly News)

“It’s as exciting as the discovery of Lucy because it’s comparably as complete as Lucy’s skeleton, it’s older than Lucy, and it takes us back to a very early stage in human evolution when we were really close to the common ancestor we had with the chimpanzees.” (BBC)
 
Scientists recently announced the discovery of the oldest, most complete ancestral human skeleton to date. The discovery is hailed as groundbreaking, but some scientists question whether she’s really relevant to human evolution.
 
The original researchers say Ardi has overturned several theories on what the earliest two-legged ancestors of the modern human looked like, and where and when they might have evolved to walk upright.
 
Kent State University's C. Owen Lovejoy did lab analysis on Ardi’s skeleton.  He says Ardi also surprised researchers when it became clear that she did not resemble a chimpanzee.
 
“If you were to ask someone on the street today, 'What did an early ancestor of humans look like?," they would probably say that it would look like a chimpanzee. Those conclusions are very incorrect.” (ABC News)
 
“These fossils, however, show in many ways that apes evolved from humans.  Indeed, what seems most ancient about non-human primates today – canine fangs, long limbs with hooked fingers made for swinging through trees, and hands designed for knuckle walking – may actually be the product of more recent development.” (The Wall Street Journal)
 
In Science magazine, Ann Gibbons highlighted several disputes that have been raised. She spoke to several scientists around the country for their opinions, including a paleoanthropologist at the University of Missouri -- Carol Ward.
 
“Some are skeptical that the crushed pelvis really shows the anatomical details needed to demonstrate bipedality. The pelvis is ‘suggestive’ of bipedality but not conclusive.”
 
An anthropologist gives his take on NPR’s All Things Considered.
 
“What I’ve not seen is anything that really convinces me that it’s the ancestor of modern humans.[…] We know if you look at the rest of the tree of life, the minority branches reach the surface. Most of the branches never make it.”

Smithsonian freelance science writer and blogger Brian Switek offers an even-handed summary of the conflict over classifying every hominid skeleton as one of our ancestors.
 
“We want to know whether this or that early hominin was ancestral to us, but in many cases we cannot know for sure. I have no doubt that there are plenty of other early hominins to be discovered, and as they are found, I would expect a ‘bushier’ picture of human evolution to emerge.”
 
So what do you think?  Are you surprised by the revelations about Ardi?  We'd love to hear your thoughts in our comments section below -- and be sure to check out our transcripts.