The article is about an exciting new scientific story about the reconstruction of the the skeleton of a 4.4 million-year-old hominid, the biological line one branch of which led to modern humans (homo sapiens): Long-Awaited Research on a 4.4-Million-Year-Old Hominid Sheds New Light on Last Common Ancestor Scientific American Online by Katherine Harmon 10/01/09; Ethiopian desert yields oldest hominid skeleton by Robert Sanders, UC-Berkeley Media Relations 10/01/09; Before “Lucy,” There Was “Ardi”: First Major Analysis of One of Earliest Known Hominids Science by Kathy Wren10/01/09.
One reason for the excitement is the unexpected features the skeleton, dubbed "Ardi" but scientifically designated as Ardipithecus ramidus, has revealed. As Harmon reports:
Ardi is, in fact, "so rife with anatomical surprises, that no one could have imagined it without direct fossil evidence," wrote C. Owen Lovejoy, a professor of anthropology at Kent State University in Ohio, and his colleagues in a summary of one of the papers.Sanders writes of this research:
Among the surprises: Ardi's jaw and limbs show she was a forest-dwelling omnivore, not a fruit-eater like today's chimps or an open savanna–dweller like other early hominids. Ardi had a brain about the size of a modern chimp's relative to body size (about a third the size of a modern human's). And Ar. ramidus's foot is strikingly unlike that of a modern chimpanzee, the authors of another paper (led by Lovejoy) explain.
The female skeleton, nicknamed Ardi, is 4.4 million years old, 1.2 million years older than the skeleton of Lucy, or Australopithecus afarensis, the most famous and, until now, the earliest hominid skeleton ever found. Hominids are all fossil species closer to modern humans than to chimps and bonobos, which are our closest living relatives. ...Harmon explains what also makes this an important example of how science works:
The team's reconstruction of the 4-foot-tall skeleton and of Ardi's environment — a woodland replete with parrots, monkeys, bears, rhinos, elephants and antelope — alters the picture scientists have had of the first hominid to arise after the hominid line that would eventually lead to humans split about 6 million years ago from the line that led to living chimpanzees. [my emphasis]
Like any significant scientific discovery, Ar. ramidus raises more questions than it answers. "It's going to keep generations of students busy," CASHP's Richmond says of the research. It will also likely usher in a change in the common understanding that modern humans descended directly from chimpanzees — as popularized by the illustrated "quadrupedal monkey to upright man" sequence. Accepting the new view of human evolution that the Ardi analyses suggest, says Ward, will mean "tearing that [depiction] up and throwing it out the window."Richmond may be a bit optimistic. Because the current "common understanding that modern humans descended directly from chimpanzees" was different from the already-established paleontological view that humans diverged from the line that led to chimpanzees around six million years ago.
But the new discovery provides new clues to how and when two legged mobility and paternal involvement with offspring evolved.
Eric Young's Christian Post article, however, provides a good example of the shameful way creationists promote hostility to science among Christian believers with whom they have credibility. Young reports in the first few paragraphs on the discovery itself. He then radically misstates the significance of the discovery's significance:
Simply put, this means the new skeleton reverses the common understanding of human evolution. Rather than humans evolving from an ancient chimp-like creature, "Ardi" provides evidence that chimps and humans evolved from some long-ago common ancestor - but each evolved and changed separately along the way.The most generous interpretation of that is that he didn't understand what he was hearing and reading about the find. This is a good example of how to give a wrong impression without technically saying something incorrect. Yes, the find does provide more evidence "that chimps and humans evolved from some long-ago common ancestor". And if the "common understanding of human evolution" is that humans evolved from chimpanzees, it could possibly change that. Or not, as discussed above. But if it "reverses" that common understanding, wouldn't that mean that people would now understand that chimpanzees evolved from humans? Young leaves the impression - without actually explicitly saying so - that the Ardi discovery is the first evidence that humans and chimpanzees diverge from a common ancestral line, rather than humans evolving from chimps. But that recognition of a common ancestor has been around for a while. Harmon writes:
The analysis of Ardi gives new poignancy to the notion, set forth nearly 150 years ago by Charles Darwin and Thomas Huxley, that there was likely a common ancestor quite different from both modern humans and great apes. Darwin knew, White noted in the recorded interview that, "the only way we're really going to know what this last common ancestor looked like is to go and find it." [my emphasis]Young then proceeds to write:
Following Thursday’s announcement, some critics of evolution theory used the latest buzz to point out that “faith” is required to believe pro-evolution scientists who are themselves unsure about many things and constantly changing what they believe to be true.Comfort's comments are dishonest on more levels that one. Unfortunately, it's common for Christian fundamentalists to try to dismiss the entire enterprise of science by denigrating it as simply one point of view. Comfort's particular twists denigrates both science and religious faith by encouraging his listeners to dismiss evolution because it is based on faith.
"’Six months ago, we would have said our common ancestor looked something like a chimp,’" Christian preacher Ray Comfort cited White as having said. "’Now all that has changed.’ Sure has. And it will change again, and again, and again. I know, ‘that's what real science does.’”
Comfort, who has been drawing attention and controversy this past week for his plan to distribute tens of thousands of anti-evolution books to university students, said he needs “hard evidence,” and for him, that comes from Christianity.
“I know where we came from (on the highest Authority), I know why we are here and I know where I am going after death,” he stated Thursday.
“[I]t’s hard to argue with the sort of devotion that evolutionists have,” Comfort added, calling the findings of the Ardi researchers a “faith matter.”
Out here in the real world, of course, the theory of evolution - and the findings about "Ardi" - are based on evidence, not faith.
But his argument is a common one among fundis when he refers to "scientists who are themselves unsure about many things and constantly changing what they believe to be true". This reminds me an anecdote about the economist John Maynard Keynes, who was challenged by someone for having changed his opinion about something or other. Keynes replied, "When the facts change, I change my mind. What do you do, sir?"
One might even say that the need to constantly re-evaluate specific assumptions based on new relevant evidence builds a kind of humility into the process of science. Though there is abundant evidence that individual scientists are sometimes now blessed with excesses of humility.
Such humility is also relevant to religion and theology. If a Christian minister or theologian comes to realize that the way he has been interpreting some aspect of Christian belief and practice has been inadequate or wrong, shouldn't he, you know, change his mind? Like Martin Luther, to take just one example? Changing your mind based on new and better information isn't just a scientific way of thinking. It's a grown-up way of thinking?
But the quotes there from Ray Comfort express only one side of the Christian fundamentalist attitude toward science, the side that says that faith (specifically the fundamentalist version of the Christian faith) trumps science. Since it began in the 19th century, Christian fundamentalism has also insisted that science actually supports the fundi version of the world, which requires reading the Christian Scriptures like a science text. And even that requires quite a bit of imagination.
The outcome of this strange mixture of approaches has been in practice to reject real science, embrace junk science and promote an untenable version of Christian theology.
Simon Maloy at Media Matters has more in Pulling fossilized heads from the sand -- and burying live ones in it 10/05/09. He includes information on the crackpot connections of Ray Comfort, which the Christian Post didn't think its readers needed to know in their article. I would say that Maloy could have described the meaning of "theory" in science a bit better. Creationists play on a quirk of English in which "theory" is used colloquially to mean something like a guess, as in "that's just a theory". A scientific theory is a systematic description that consistently explains the given facts of a topic. Discovering something new that may superceded one theory doesn't mean the earlier one was false. Newton's theory of gravity doesn't explain as much of the universe as Einstein's theory of relativity, which says among other things that gravity is a result of the fact that spacetime is curved. But (with some exceptions for the outer planets), Newton's theory of gravity still explains how gravity works in this solar system. That famous (if maybe apocraphal) apple still falls to the ground. But Albert Einstein had better telescopes than Isaace Newton did. So he could make factual observations that were inaccessible to Newton.
Tags: christian fundamentalism, christian right, christianism
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