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> [Being an expert] doesn't mean that you're not making a misstep here. That’s correct, but we’re not discussing the cutting edge here but relative basics. I’m
by klmr 7y ago
> [Being an expert] doesn't mean that you're not making a misstep here.
That’s correct, but we’re not discussing the cutting edge here but relative basics. I’m clearly not articulating myself well but I can assure you that this discussion wouldn’t take place between two biologists because there’s nothing here.
> It should be noted that I never said directional -- I actually made it explicitly clear in my first post that I was not arguing for a direction
You did say that, but, respectfully, you implied directionality — otherwise it would be completely unclear what your initial comment wanted to say, because it seems to specifically have objected to my assertion that no directed changes of the germ line exist.
> Do we agree that random mutations of the germline can result in differing rates of change across subsets of the genome?
Not within a single generation, no. Across evolutionary time, by virtue of selection, yes (that’s in fact the very basis of evolution). But this is irrelevant in the context of this comment thread, started by my initial comment: I asserted that there is no mechanism to encode learned behaviour in the germ line. This would require a direct mediator of mutations on the molecular level, not across evolutionary time but in the here and now. A molecule in the gametes (or their precursor cells). Such a molecule does not exist. Stochastic variation that shapes patterns of mutation across multiple generations is fundamentally a red herring here.
- blotter_paper 7y ago> You did say that, but you meant directionality — otherwise it would be completely unclear what your initial comment wanted to say, because it seems to specifically have objected to my assertion that no directed changes of the germ line exist. No, I did not mean directionality. I meant what I said, and was very explicit about it. In my first post I quoted the exact bit of your comment I was replying to, which went like this: "So far there’s no known mechanism for systematic, guided DNA changes, and no good reason to assume that such mechanisms exist (on the contrary)." I wasn't even sure if there would be disagreement between us when I originally replied to that, because I'm not sure how broad the definitions you're using for "systematic" and "guided" are. I could see arguing that evolution changing the variability of a subset of the genome is "guided" in some sense, as it can "guide" the process towards more changes in a particular subsystem, but I could also see not arguing that since it lacks direction. Language is mushy. I was trying to qualify your statement, and I posed questions and made statements of my own to that end, but I wasn't sure if my positions were in conflict with yours until you replied. Now I think our positions probably weren't in conflict, but you made assumptions about what I meant to convey based on the larger context of your own post rather than the actual content of mine.
- klmr 7y agoSo, to clarify, in that comment by me, “guided” (and, in fact, my whole comment) definitely implies “directional”. But let’s not get hung up on this one word. The comment was about encoding learned experience in the DNA of gametes (i.e. Lamarckism), and the fact that this requires a (nonexistent) mechanism.