Ida - the 'Missing Link'?

As you might recall, there was quite the hubbub about the fossil named 'Ida' a couple of weeks ago. Many websites along with the twittering public (including myself) proclaimed this fossil to be the 'missing link' and claimed it as a score for evolution in the ongoing battle between evolutionists and creationists. Some people went further and not only claimed it as a win for evolution, but the win for evolution. Some of this commotion has died down, and I think the subject requires reconsideration.

I have been thinking about evolution lately because I am currently reading The Ancestor's Tale by Richard Dawkins. This book will be featured in an upcoming review so I won't discuss its specifics here, but it has made me reconsider what I know about evolution and what I still need to learn. It's not that I don't know how evolution works, or that I forgot how it works. It all seems pretty clear to me, but these things can get muddled when you go many years without reading an advanced or even intermediate discussion on the subject.

Opinions about this fossil were pretty varied when it arrived, even among my friends. Many people proclaimed 'this is the Missing Link, suck it creationists!', where many other people met it with indifference. Of course there is still the 'dinosaur bones were put in the Earth to test our faith' contingent and you can imagine how convinced they were at this being our ancestor. My new opinion is that everyone in the camps listed above was wrong. The very term 'Missing Link' misconstrues what evolution is all about; gradual changes in multiple species at the same time for them to better survive their current environment. The term 'Missing Link' assumes there is something different about us and the rest of life on this planet, more specifically us and the other great apes. Originally it was thought that we are so different (and superior) to chimps, apes, and all other life that there must have been something about our evolution that we didn't fully understand. These of course are ridiculous claims. There is nothing special about our evolution, or our branching off from the chimpanzees. In fact we are closer to chimpanzees than many other similar looking animals are to each other.

The term 'Missing Link' also denotes the incorrect idea that evolution is a progression. Many people feel this way, and thus incorrectly assume that this progression has led the animal kingdom to the homo sapiens. We are not the 'goal' of evolution. Humans are just one of the many evolutionary branches that happen to be quite successful (we are not even necessarily the most successful, lets ask cockroaches what they think). It's not that chimps are our ancestors, and where they stopped evolving we kept going. We both have a common ancestor that we broke off from and kept evolving. We decided (of course we didn't decide to do anything, it just happened to be advantageous for our situation) to go bipedal, hairless, and grow a bigger brain. This does not mean that chimps are 'primitive' compared to us, in a way they are equally evolved.

This is where Ida comes in. Just looking at the fossil you can tell that she is not the 'Missing Link' between humanity and the apes. She looks nothing like an ape! Ida resembles something like a Lemur, which are our closest cousins after all apes and monkeys. Thus at a point (some 63 million years ago) we shared an ancestor with the lemurs. This does not mean that it looked like a lemur (it could have) and then at that point lemurs stopped evolving and our line kept going.

Ida is not this common ancestor, and most likely is not an ancestor of ours at all. Because the evolution 'tree' branches off very rapidly there are many species that may 'look' like our ancestors but are actually ancestors of some extinct species. This is most starkly seen when we consider Neanderthals. We did not 'evolve' from Neanderthals, our ancestors actually lived at the same time as them! Eventually they went extinct (many people think we wiped them off the face of the Earth) and we now have fossils that look fairly 'human'. Species branch off and go extinct all the time, so it's almost impossible to say if any fossils we have found are actually ancestors of living species. However fossils are useful for us to see what kind of species our ancestors may have resembled, and radioactive dating (among other methods)gives us good dates for these developments. A good description of the way evolution works and how this relates to Ida by an angry and silly nerd can be found in this video.

So what is Ida if she is not our ancestor, or even the ancestor of lemurs or other living creatures? Because of certain bone characteristics it is known that she comes from our side of the branching off from lemurs. Thus Ida can be seen to be a step in the evolution between the common ancestor we hold with lemurs (which likely looks like a lemur given Ida's appearance) and the monkeys, gibbons and apes that follow. She may be our direct ancestor, or is more likely a branch of species that long went extinct.

This does not mean that Ida is not an exciting find. It's a very old, intact fossil that comes from our branch of evolution. It helps to complete the very sparse puzzle that is the fossil record, even though we will never have enough fossils to 'fill in the gaps'. Paleontology is a tough gig, we have to use what we find, and it's often not what we 'need'. Ida is a very exciting discovery, but it won't help to convince anyone who already questions evolution more than previous fossils or the mounds of genetic evidence we already possess.