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So I wasn't in Prof. Dalke's section on Thursday, but I wish I had been for the discussion on Evolutionary Error (not at all to knock P. Grob's section, which rocked on out complexity and homeostasis). I think that in some sense, we are all errors. Genetic mutations can occur in any number of ways, but one of the most common is due to infidelity of enzymes involved in DNA transcription (the process of turning DNA into RNA) or replication (the process of reproducing DNA for meiosis I or mitosis). So what that means is that a great deal of appreciable biological variance is effectively the result of a molecular error in copying, a little splotch on a Xerox. While this might not apply to, say, the engendering of eukaryotes by the endosymbiosis, it could certainly apply to the development of different beak shapes that Darwin observed in the Galapagos finches. A couple birds had screwy proteins that made them better adapted to the pressures of natural selection, and it was that mistake that made them better able to survive.

While Gaby raises a valid point that we can't be errors if we survive, that particular viewpoint doesn't really jibe with the way that I'm thinking about evolutionary error. I think that there are lots of errors in transcription and replication that can occur that won't necessarily impact an organism's capacity for survival, especially in human cultures where a docile dog can survive as a pet and flowers are bred to be pretty if not easily pollinated.

Furthermore, I wonder if there's something more to be made of human infertility. If a person cannot reproduce, but is able to raise someone else's children, doesn't that take some measure to ensure the perpetuation of the species? Or on an even larger scale, if an ER doctor develops testicular cancer and can't have children but saves 100s of lives through his work, does that mean that he can't have a part in the continuance of the human race? I guess what I might be saying is that maybe infertility is equivalent to apoptotic death in cells - a kind of taking one for the team.

Katie Baratz