I was talking to my brother John the other day about how it’s commonly assumed that we know almost everything about science, so there isn’t much left to discover. Specifically, there’s this notion that new discoveries aren’t likely to overturn older ideas, because if so someone would have done so by now. I personally think that’s complete hogwash; my favorite saying about the scientific method is, ” Progress consists of replacing a theory that is wrong with one more subtly wrong.” Ideas derived scientifically are certainly useful, but they shouldn’t be considered inviolate.
In that vein, it’s nice to see scientists continue to push the boundaries of what we assume, as in this article by Derek Lowe about DNA sequences that are identical in humans and mice:
Even important enzyme sequences vary a bit among the three species, so what could these pristine stretches (some of which are hundreds of base pairs long) be used for? The assumption, naturally, has been that whatever it is, it must be mighty important, but if we’re going to be scientists, we can’t just go around assuming that what we think must be right. A team at Lawrence Berkeley and the DOE put things to the test recently by identifying four of the ultraconserved elements that all seem to be located next to critical genes – and deleting them.
The result? No detected difference in the mice, and a whole lot of speculation as to how that’s even possible. The results can be (and are being) debated furiously, but the point is that there’s something completely unexplained that, when tested against prevailing knowledge, doesn’t match up. To me that’s not just noteworthy, it’s exciting! It means there’s a lot more exploring to do, a lot more science for all of us.
 I’ve seen this one around the tubes, generally attributed to Dr. David Hawkins. If you know of a linkable source, post it in the comments.