I’m working my way through a pre-publication copy of a book called God and Country: America in Red and Blue, by Sheila Kennedy. This book examines many of the culture war issues in America and starts from the premise that we must recognize that on many of those issues, the two sides begin from radically different starting points. I was reminded of that as I’ve watched the reaction to this article about a new study on whether Australopithecus afarensis is a direct ancestor of modern humans or an evolutionary cousin.
This new study uses comparative morphological analysis between the Lucy specimen and various modern primate species, including humans, and found that one particular morphological feature (the mandible where the jaw and cranium connect) was common among those species more distantly related to humans (gorillas) but missing in our closer relatives (chimpanzees). Thus, they argue, this casts doubt on whether A. afarensis was a direct ancestor of humans.
The moment I saw it I knew that we would see it rapidly disseminated on creationist webpages with declarations of “A ha! You see, evolutionists had it wrong!” And sure enough….here’s DaveScot ignorantly declaring that “Icon of Evolution Lucy Bites the Dust” at UD. The folks at Free Republic jumped all over it. ARN did too. Expect it to show up on many more creationist pages soon. But before this uninformed and pointless crowing goes too far, a few things need to be said.
First of all, like most popular press reports of scientific studies this article vastly overstates the findings of the study and turns complex and nuanced conclusions in to simplistic and breathless declarations. The first line of the article decalres that the scientists who did the study “say they have disproven the theory” that Lucy is a direct ancestor of humans. But if you bother to read one paragraph later you find a far less strident and more nuanced statement from the scientists themselves:
The specific structure found in Lucy also appears in a species called Australopithecus robustus. Prof. Yoel Rak and colleagues at the Sackler School of Medicine’s department of anatomy and anthropology wrote, “The presence of the morphology in both the latter and Australopithecus afarensis and its absence in modern humans cast doubt on the role of [Lucy] as a common ancestor.”
I dare say the phrase “casts doubt” is a far cry from “disproves” and the difference is quite important when dealing with science. Scientists rarely speak in such bold terms, especially about a subject like ancestral relationships and even more so about a field where we have an incredible array of extinct species, some of which lived at the same time and where the morphologies are so overlapped on so many traits that it has become very difficult to determine which particular ones gave rise to which others.
But the fact that they crow about it anytime a minor hypothesis is disputed and shout any and all disagreements from the rooftops to sow doubt about science as a pursuit of truth indicates a deeper conflict here, as Sheila Kennedy would remind us. We simply do not start from the same epistemological premise because the creationists begin from a fundamentalist mindset that says that truth is revealed, not discovered. The differences between this epistemological approach and the scientific approach are many.
From their perspective, truth is revealed to our feeble minds by a being with perfect knowledge. Revealed truth, therefore, cannot be wrong, not even in the tiniest details; if it is, then all of it is disproved and the revelation could not possibly have come from its putative souce. This is in stark contrast to a scientific approach that is based on constantly and relentlessly proposing and testing hypotheses, continually refining our explanations by discarding those explanations that don’t work and always testing accepted explanations for their consistency with new evidence.
The problem is that the anti-evolution crowd views the theory of evolution (which is really an immense bundle of theories and hypotheses, some of which are well established and some of which are still highly contentious and will eventually be discarded or confirmed) as an instance of revealed truth. Thus their obsession with referring to those who accept evolution as “Darwinists” – to them, evolution is revealed truth from Darwin and if any particular hypothesis within the larger evolutionary umbrella is shown to be false then that proves that this revelation came from a false God.
Scientists, of course, don’t think in such terms at all. Darwin was a great scientist and he left us with a basic model that continues to explain the natural history of life on earth quite well despite being incomplete and, on some details, inaccurate. A scientific theory is not revealed truth, it is an ongoing collaborative project involving, in this case, tens of thousands of scientists, constantly working out the details of a vastly complex model that involves millions of species and a dozen fields of inquiry.
But to the creationist mindset, to quote Robbie the Robot, this simply does not compute. If truth is revealed, then it is unchangeable and immutable; to refine, then, is to negate. For the creationist, every argument is an argument from authority and every dispute a dispute between two competing faiths. Thus the ubiquity of creationist attempts to cast science in religious terms with phrases like “Darwinian priesthood”; they simply cannot conceive of an argument that is not based on revelation and authority. And this is why they crow so loudly whenever any scientist challenges another scientist’s position or when any proposed explanation is shot down. And since science eventually rejects at least 9 out of 10 proposed explanations, they will never run out of ammunition for this argument, no matter how ignorant and toothless it may be.