Putting Ida Fossil in Perspective, Putting Creationists in their Place
The above painting is one of the better illustrations aimed at laypeople that I’ve come across for getting a sense of what’s at stake in terms of fossil finds like Ida (Darwinius masillae). And, more importantly, given the media circus, what’s not at stake.
Note the dots in the highlighted area. A fossil like Ida (though, not specifically Ida: a similar picture would have her highlighted section/branches farther down to the left) could be any one of those dots. We can’t yet be sure which. And the ancestral line that leads more directly down the branch to apes and eventually to humans could also follow nearly any time-linear path through the dots in that area as well. More likely than not, Ida is not herself part of that particular direct line of ancestry (certainly not her specifically, since she died so young, and not likely any member of her species either). She may even be a dot so far off the main branch as to have existed long after that direct line diverged from her entire branch of primates.
Which doesn’t mean that Ida can’t tell us anything about humans and their evolutionary history: she can. While most of her features were known long to be part of primate history long before yesterday’s announcement, she is one of the best specimens we have to help date the development of these features and understand how they fit into the overall pattern of traits we see emerging in early primates over time. The clearer that overall picture gets, the more we know about where the ancestors of humans fit into it, even if we never find a single fossil of a species more directly in the path of our eventual ancestry. That may seem less exciting than “THE missing link!” headlines, but honestly, it’s actually more exciting. Because it actually means something.
We can excite the public about science without misinforming them. We can. There IS good science journalism out there, and it IS exciting and eye-catching when done right, without being flat out inaccurate. And we have to start demanding it, even from the increasingly tabloid-esque cable news industry.
I have little doubt at this point that creationists will seize on the irresponsible rhetoric surrounding Ida to make their case that fossils can’t tell us anything about evolution, and that this one fossil doesn’t “prove” anything. Answers in Genesis is already on the case And in some ways, they’re actually right: this fossil by itself doesn’t necessarily “prove” anything about common descent or evolution. But as long as they continue to deal with each particular fossils in isolation, they’re distracting people from the big picture, into which a fossil like Ida fits perfectly. And that’s a picture that really only makes any sense at all in light of common descent.
The idea that we’d expect to find a creature akin to a “half lemur/half ape” is a grotesque misunderstanding of just what “transitional” means in evolution, and yet AiG spends a lot of time crowing about the lack of these sorts of “real” transitional forms, completely missing what’s right under their noses. Ida and nearly every other primate fossil we have are all chock full of transitional features that show distinct and cross-confirming patterns of progression and divergence over time, especially when placed into context with each other and the rest of the fossil record. Every new fossil that we’ve found to date falls into this intricate pattern of traits, even down to them appearing in the timeframes and geographical locations we’d expect… if and only if we were looking at physical lines of descent that happened via a distinct historical sequence of events.
How do they explain it? They don’t. They can’t. They’re left with lame “well, it looks like any old lemur” excuses that involve squinting hard enough to ignore both the key differences and the over pattern they paint. And that’s because once you really confront the reality of the fossil record, you’re left with either putting it down to a incredibly implausible coincidence or, even more embarrassing, a designer so enamored of evolution that it decided to create creatures ONLY such that they could be fit into a discrete family tree, without ever breaking the pattern (as would be simple to do, and as human designers do all the time with their non-ancestrally related constructions).
Or, finally, admitting that, if it’s possible to show evidence of anything at all, then we already have incredibly sound evidence for common descent: to a cross-confirming degree of detail that dwarfs most other natural knowledge.
Ida is controversial and interesting to scientists primarily because she can help us map out the particular order and relation of those dots above. But in terms of evolution as a whole, she’s simply one more nail in a creationist coffin that’s already been sealed and buried for nearly a century now.