You'll recall (hopefully) Ardi, the Ardipithecus ramidus, an ancient human ancestor that's recently gotten a whole lot of media attention. Excellently pseudo-named blogger Zinjanthropus (actually a mild-mannered biological anthropology grad student) is doing a series of posts that take a close-up look at some of the biological quirks that make Ardi such a surprise.
The first post is on Ardi's hands...
The extant African apes are knuckle-walkers, they have stiff, inflexible hands and wrists that allow them to support their body weight in sort of a weird position. Because they also have to climb trees for food and protection, their hands are very long and powerful. Humans, on the other hand, have pretty mobile hands and wrists which allows us what we call a "power grip." We are very good graspers, and this has allowed us to become the dexterous tool-wielders that we are. Because of our close genetic similarity to chimps, and the close morphological similarity between chimps and gorillas, it has been argued that certain features of the Australopithecine wrist- and even the human wrist- were "hold overs" from the period of time when we, too were knuckle-walkers who required a stiff wrist and hand.
However, Ardi's hand more closely approximates the human hand than the knuckle-walker hand.
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The media attention to this has been hilarious. So many banner headlines shouting "This proves our ancestors were not chimpanzees!"
Um... We knew that. No existing species is our ancestor.
Ok, so they were close: this proves that our ancestors were less chimpanzee-like than we originally thought. But by that point, the damage had been done:
Ardi Proves Darwin Wrong! Ardi proves we're not descendant from Monkeys! Ardi proves we're not apes! Ardi proves that evolutionary scientists got it wrong again!
The noise from creationists after this has been hysterical.
So much agreed, SamSam. That's actually why I linked to the Knight Science Journalism Tracker for the news on this, rather than any of the actual articles, themselves. That page provides some sanity and context that most of the reporting missed...plus they link to the reporting that's actually worth reading.
Still. Yeah. This whole thing has been head-desk city. Even some of the quotes from the actual researchers seemed poorly thought out.
One of the many things I love about the discovery of the whole range of ancestral fossils is how wrong the early, few-or-no-fossil theorists were about the specifics of human evolution (like the big-brain first ideas that let piltdown be so acceptable) and how relatively easily those ideas fell as contrary evidence came to light, Dubois and others notwithstanding.
How refreshing it is that humanity has developed a mechanism by which observed reality can result in major changes in worldview without people killing each other over it. Now if we can just get more people to understand the methodology...
It really is a shame that reality poses such a threat to some peoples worldview. Nice post, SamSam. (and of course, Maggie)
You might be interested in a piece I did at Psychology Today pointing out several errors in one of the Ardi papers published at Science:
http://www.psychologytoday.com/blog/sex-dawn/200910/did-monogamy-begin-44-million-years-ago
Another good piece is at:
http://scienceblogs.com/primatediaries/2009/10/science_got_ardi_wrong.php
Ack! Sometimes I think we need a specialised subset of science devoted to good experimental practice only -- no studies with less than 100 subjects, no esoteric results, a clear grasp of the differences between correlation and causation. Real scientists know their limits, and the difference between scientific results and wishful thinking.
It would be a short list, so one could read all of it if they were so inclined, without having to sift through all the garbage.
While I agree that science articles often have methodological errors, I don't think the problem would be fixed by limiting sample sizes to 100 plus. Firstly, you're going to chuck out most psychology research (including my own - I'd like to see someone recruit more than 100 people with dementia willing to perform full neuropsychological testing in the period of an average PhD). Also, if you're using standard statistical techniques that favour significance testing, you're going to increase your type I error rate - the chance of finding significant differences that are spurious - mainly due to increased N which reduces the difference needed to be statistically significant.
I propose that all researchers (at least in the social sciences) use effect sizes to demonstrate the clinical significance of their findings. Also more Bayesian analysis would be good - but I don't see that one happening any time soon.
100 is as arbitrary a figure as any other. Just because it's the square of the number of digits on the upper limbs of a great ape doesn't mean that it's significant from a statistical point of view.
Wow. The Pope's not going to want to hear about this.
Actually, my understanding is that the Catholic church has a pretty progressive attitude about evolution, officially accepting it as the way that God could have directed creation. I could be wrong on that, but it's what I've heard from Catholics.
Just a couple of days ago I watched a talk given by, among others, the "chief astronomer of the Vatican" (who knew?) about cosmology and extra-terrestrial life. He was pretty much right down the line in agreement with mainstream scientific belief, just throwing god in with an ontological argument at the end...
As Anonymous above, I must say that this subset I propose would exclude the social sciences by definition, as the only types of truly testable experiments in that field would require Tuskegee levels of behavior, and no one wants that.
The reason I said 100 is just a reaction to the kind of article that stresses 40% response throughout, and only admits there were only 5 participants once.
Not saying not to do these experiments necessarily, just that their status as partly anecdote, creative writing, philosophy, extrapolation or confirmation bias makes them less interesting when one is looking for mathematical scientific proofs. I understand that this too is a bias, but one that would have quite a niche.
I have a similar bias in fiction -- they lump together science fiction and fantasy in such a way that in order to reach any book or story I'm interested in, I have to flip through 20 dragons, chicks in chainmail, and elves first. Then another 20 to the next and so on. It's about relative volume. At least scientific journals are pre-sorted by subject!