[Southack]

"The odds of the mutation appearing in subsequent offspring? The "expected value" is 100%, in a species that is neither growing significantly in population nor declining, although the actual results can vary from zero offspring carrying the gene, to a large number depending on the fecundity of the species. On average, though, the gene will be passed on to one offspring by each parent that carries it. ... Try to keep up with the discussion, Maro was specifically trying to calculate the odds for a combination of mutations which, and I quote, "make no functional difference". This is quite a different situation from your cheesy example of two-headed snakes, which are obviously a detrimental mutation which inhibits both survival and reproduction." - Dan Day

You'll have to explain to me how the "expected value" for the probability of a mutation being passed to offspring is 100% when you admit that mutations such as two-headed snakes WON'T propagate to their offspring.

[Dan Day]

You'll have to explain to me how the "expected value" for the probability of a mutation being passed to offspring is 100% when you admit that mutations such as two-headed snakes WON'T propagate to their offspring.

Because detrimental mutations like having two heads strongly tend to be weeded out (by interfering with propagation), whereas neutral mutations (the sort being discussed) don't.

It's apples and oranges. Different forces are at work on each, and thus it's no surprise that the results will differ.

I even pointed that out in the part of my post which you quoted in your post, try actually reading it next time.