Timothy Standish offers us some thoughts on that microbe (a protist, Carpediemonas membranifera) that, without being a parasite, lacks most of the molecular equipment needed to kickstart DNA replication (and no one understands how it does that):
It occurs to me that if I was a Darwinist, I’d be all over this, saying things like, “Look, we can see that organisms survive perfectly well without all the stuff you ID types think is essential. This shows that organisms can evolve from much simpler forms.” It surprises me that I’ve not seen anything like that, but often enough complexity comes first followed by simplicity made possible by further advances.
Turbine engines are a great example. Internal combustion reciprocating engines got progressively more complex before the quantum leap to jet engines, but this didn’t really happen in one huge jump, it was the combination of steam turbine engines, internal combustion and a whole lot of fancy metallurgy that everyone forgets that came together in the mind of Frank Whittle and some others. But what a huge leap going from basically thousands of moving parts to a single moving part that produces more power for less weight.
Note that while some may see this as a kind of evolutionary process, the huge leap took a brilliant mind. I suspect the same principle is true in living things. Simpler systems do not necessarily come first because simple can be a lot harder to come up with than complex. Yes, that seems counterintuitive, but the history of technology bears that out. In some ways you could say the same about art.
Before getting too carried away down this track, one should also keep in mind that organisms as they exist are amazingly robust. Humans can survive after the removal of quite a few important organs ranging from the thymus gland to the spleen. This isn’t an indicator that these organs lack function, it is an indicator of just how robustly organisms are designed.
The mechanism that is being used to begin DNA replication in this microbe may not be what we have come to expect from other living things that have been studied, but DNA must replicate, so an initiation mechanism must exist. If it isn’t the mechanism used by other organisms, it may call into question the logic that says shared mechanisms are evidence of shared ancestry. Or maybe there is some backup mechanism we are unaware of and this is an example of the devolution that Mike Behe has pointed out as a major mechanism of adaptation.
Whatever the explanation, the most important quote in the article came from Dayana Salas-Leiva, “I was astonished.”
So was I!
See also: At New Scientist: “single-celled organism that lacks most of the molecular equipment needed to kick-start DNA replication” It’s a protist? “Protists are a group of loosely connected, mostly unicellular eukaryotic organisms that are not plants, animals or fungi. There is no single feature such as evolutionary history or morphology common to all these organisms and they are unofficially placed under a separate kingdom called Protista.” In short, just the sort of life form that might be doing something really different. Because nature is full of intelligence, there are probably many alternative programs out there. It all didn’t just somehow happen randomly once.