Jeffb asks for examples of beneficial mutations

Virulence cannot be reduced to mortality. It includes morbidity.

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Sure. Let’s see if we can figure out how far to extend the x-axis to the right so we can place a 50-60% increase in transmissibility mutation. I’m pretty sure a mutation with an effect of that magnitude shouldn’t even exist according to Sanford. One has to wonder when mutation are supposed to result in a net fitness loss if mutations of beneficial effects of such magnitude keep occurring. 100 million years from now?

SanfordCurve

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Here’s another fine example of beneficial mutations at the protein level:

McCracken KM et al. 2009. Signatures of high-altitude adaptation in the major hemoglobin of five species of Andean dabbling ducks. Am. Nat. 174(5):631-50.

Of course one can’t say these are mutations unless one allows that ducks are related by descent. @jeffb needs to define the limits of the “kind” before we can talk about most of the evidence for such things.

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You and I both know this % increase number is probably reckless. It’s based on modeling, which could be a founder effect or chance. There’s some information it is more prevalent in kids so I wonder if it gained function to infect kids more readily. That means there’s a huge population that wasn’t getting infected very easily but now is. Anyway, there’s too many unknowns to draw conclusions. It may not even have increased fitness at all and it could all be hype. I’m doubting that too, but it’s still within the realm of possibility.

I would anticipate this will fall under the Jeanson’s speciation by heterozygosity. So then a YEC “duck baramin was created with high-altitude heterozygosity genes in reserve” clause. Voila, variation with limited common descent, unstained by beneficial mutation.

Don’t forget to also narrow the “No Selection Zone” from an effective population size of ~10^3 to an effective population size of ~10^7.

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We don’t, but I’d be happy to say the number is subject to change as more data is collected.

Of course, even at a mere 10% increase it’s still essentially outside the realm of possibility given Sanford’s “Correct distribution”. You’d have to extend the x-axis to be over 50 times wider than what is shown. Please try to calculate the probability of a mutation with a fitness effect of 10% given an exponential decline, with that depicted curve for beneficial mutations Sanford has drawn inside the “zone of no selection”.

At one tenth of one hundreth of a percent increase in fitness, Sanford has drawn the curve at effectively zero probability that a mutation has so large a positive effect. He clearly considers it so low as to be impossible to even show on a figure. So how infinitesimal must the probability of a mutation with a 2%, or 5%, or 10% increase in fitness be in his imagined reality?

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