Viruses mutate really fast, so lots of GE. Bacteria also mutate really fast, so no GE. But mice, with short generation times, have no GE, even though they have more generations per year than humans. GE is magic: it’s fast or slow exactly as needed for the group in question, just don’t ask how!
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They do mean what I think they mean. 
However, just to make it more explicit, let’s break this down even further.
-
Most mutations (vast majority, i.e. a million to one odds) are deleterious. We’ve established this one already.
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Most mutations are very small in their effects:
“Results from these studies have occasionally been inconsistent, but the majority
of results suggest that most spontaneous mutations have mild effects (Eyre-Walker and Keightley 2007; Halligan and Keightley 2009; Agrawal and Whitlock 2012; Heilbron et al. 2014),
that deleterious mutations far outnumber beneficial mutations (Keightley and Lynch 2003; Eyre-Walker and Keightley 2007; Silander et al. 2007), and that the distribution of effects of deleterious mutations is complex and multimodal (Zeyl and de Visser 2001; Eyre-Walker and Keightley 2007).”
Emphasis mine.
https://doi.org/10.1534/genetics.116.193060
Dillon, M. and Cooper, V., The Fitness Effects of Spontaneous Mutations Nearly Unseen by Selection in a Bacterium with Multiple Chromosomes,
GENETICS November 1, 2016 vol. 204 no. 3 1225-1238
“Mutagenesis and mutation accumulation experiments can give us detailed information about the DFE [distritubtion of fitness effects] of mutations only if they have a moderately large effect,
as these are the mutations that have detectable effects in laboratory assays. However, it seems likely that many and possibly the majority of mutations have effects that are too small to be detected in the laboratory.”… particularly for multicellular organisms … most mutations, even if they are deleterious, have such small effects that one cannot measure their fitness consequences."
[Note here that the authors acknowledge that mutations can be deleterious despite being too small to directly measure!]
Eyre-Walker, A., and Keightley P.D., The distribution of fitness effects of new mutations, Nat. Rev. Genet. 8(8):610–8, 2007.
doi.org/10.1038/nrg2146.
- Mutations that are very small are not subject to natural selection:
“In terms of evolutionary dynamics, however, mutations whose effects are very small …
are expected to be dominated by drift rather than selection.”
Shaw, R., Shaw, F., and Geyer, C., Evolution
Vol. 57, No. 3 (Mar., 2003), pp. 686-689
https://www.jstor.org/stable/3094782
See also Kimura for point 3.
Taking these three points together, it is very clear that the majority of effectively neutral mutations, just as with the majority of mutations in general, will be deleterious.
Another typical Creationist response. When called on your nonsense, just repost the same out of context quote-mined quotes.
If they are effectively neutral then they aren’t deleterious.
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Wrong: bacteria mutate much less per generation than RNA viruses do.
But mice, with short generation times, have no GE, even though they have more generations per year than humans.
I have never stated that mice have no GE. I believe they are certainly affected by it, but it will take many more mouse generations to get the same amount of GE compared to humans and other higher life forms, because they have fewer mutations per generation AND because they have much, much higher amounts of purifying selection by comparison.
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Will somebody besides me take a turn here and correct this guy? It’s too much work, and there’s clearly a major lack of reading comprehension going on.
The next time you honestly answer one of my questions will be the first. 
If you like I can repost the dozens of questions and data you’ve run from.
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Cite me a textbook where evolution is defined as an upward process. Just one reputable textbook.
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Somehow I suspect I have a better grasp of population genetics than you do.
No, we haven’t. What has been established, in lots of experiments, is that mutations that aren’t neutral are nearly always (but certainly not always) deleterious.
Yes, you already posted these, and I asked you to point out where in them the authors provided either empirical or theoretical evidence that mutations with too small an effect to be seen by selection are overwhelmingly deleterious. You haven’t done so. Posting the same statement about the same references accomplishes nothing.
I already pointed out that this paper did not study mutations with too small an effect to be seen by selection. They measure the fitness effect of mutations by comparing their fitness with wild type and seeing whether they are outcompeted. In other words, they are using natural selection to assess their fitness. Go back and read the paper’s title again.
Why the exclamation mark? Natural selection in the wild is sensitive to far smaller fitness effects than we can directly measure. They’re extending the range of fitness effects that they can measure – they’re not exploring fitness effects too small for selection to see.
As I’ve already said.
Now, I could ask you one more time for the actual evidence you claim exists, but instead, try explaining: why do you think in standard evolutionary theory (which is what we’re talking about here) a genome would ever be in a state such that most effectively neutral mutations are deleterious? How does it get into that state?
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So here’s the argument @PDPrice is making, whether he knows it or not:
- Most mutations of measurable effect are deleterious.
- Most mutations do not have measurable effect.
- Therefore most mutations with no measurable effect are deleterious.
This would work if
(Between 2 and 3). Mutations of measurable and non-measurable effect have identical distributions of fitness direction.
But of course he has no evidence for that.
But of course he has no evidence for that.
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I don’t see what that will do for this discussion. Regardless of what anybody chooses to say in a textbook, taking a single cell and developing it into a human being is very much an upward process in every way. And that is what evolutionists claim evolution is capable of!
It would show you’re not talking out of your nether regions again. But you are just repeating the usual laundry list of Creationist falsehoods, right?
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Yes. And we have strong theoretical grounds for thinking they should be different, as well as the absence of adaptive codon bias in humans as evidence that they are in fact different.
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I’m not talking what evolution is capable of. I’m talking what is it’s definition. You said it has been defined as an upward process. Earth could have been a dead planet and no complex life could’ve evolved. Doesn’t mean evolution wasn’t taking place. So I challenged you to cite a source that says it is an upward process. If you can’t do it, which you can’t, just admit you’re wrong about the definition of biological evolution.
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It’s this usual Creationist misunderstanding
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You very well may. Nonetheless, I do understand the significance of these quotes.
We can go much further than that. First of all, there is no such thing as a “neutral” mutation. Neutrality is divided into two subcategories: strictly neutral or effectively neutral. Strictly neutral mutations would have no effect on fitness at all, and thus would have no aggregate impact either. Population geneticists argue that there are essentially no “strictly neutral” mutations. That was true in Kimura’s model, and pop gen scientists continue to state the same to this day.
“… it seems unlikely that any mutation is truly neutral in the sense that it has no effect on fitness. All mutations must have some effect, even if that effect is vanishingly small.”
Eyre-Walker, A., and Keightley P.D., The distribution of fitness effects of new mutations, Nat. Rev. Genet. 8(8):610–8, 2007.doi.org/10.1038/nrg2146.
“Effectively neutral” mutations on the other hand are invisible to natural selection, but they do have a small impact on fitness nonetheless. Kimura has acknowledged that these mutations do have an aggregate impact. Kimura’s model was oversimplified, however. He did not consider the effect of noise on where the dividing line between selectable mutations and effectively neutral mutations should be placed. He also did not consider the Princess and the Nucleotide paradox. He only considered population size and selection coefficient. This means his estimated percentage of effectively neutral mutations will wind up being smaller than reality, especially for higher level organisms with more complex genomes.
Now, I could ask you one more time for the actual evidence you claim exists, but instead, try explaining: why do you think in standard evolutionary theory (which is what we’re talking about here) a genome would ever be in a state such that most effectively neutral mutations are deleterious? How does it get into that state?
I’m not concerned with “standard evolutionary theory”, whatever that means. I’m concerned with real biology. In real life, it’s much more easy to cause damage to a machine (or to the information that codes for it), than it is to improve upon it. That basic universal principle (also confirmed by the scientists in the field, in their own words) is certainly not limited to changes large enough to be detected. It’s true, period, because of the basic laws of logic and order. For this reason, we would strongly suspect that most effectively neutral mutations would be deleterious, regardless of our ability to directly test for this.
Yet you continually show you don’t understand real biology.
That’s only true if a species is well adapted and very close to a local fitness maximum in an unchanging environment. However in the real world environments are always changing and it’s not rare at all for a mutation to move a species towards a new fitness maximum.
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Actually, we have extremely strong theoretical grounds for thinking they should be the same. Entropy. Random changes generally produce chaos, not order. It is much easier to break a machine than to improve upon it. That is why your claim about codon bias is highly suspect. Codon bias is a completely different discussion from the DFE for individual mutations. Codon bias does affect things like the efficiency of translation, which means that even if it’s not a selectable loss, it’s still a loss of function:
“It seems that the major codon bias is nothing less than an arrangement that permits the cell to maximize the efficiency of translation at the fastest growth rates. Here, a special subset of proteins, coded by a correspondingly biased subset of codons can be translated by a suitably biased tRNA population in order to minimize the tRNA ternary complex mass required to maintain fast translation.”
Kurland 1991
https://febs.onlinelibrary.wiley.com/doi/epdf/10.1016/0014-5793(91)80797-7
If you want to go against both logic (it’s easier to break a machine than to improve upon it), and all the evidence from mutations we can measure, and suggest that most small mutations are NOT damaging, the burden of proof is on you to provide strong evidence for that claim. What evidence can you show? For ALL mutations we can learn about, there are virtually no beneficials to be seen anywhere. Where is your evidence that the majority of mutations (the small ones) are beneficial?
Except for the ones we do see.
4 beneficial evolutionary mutations that humans are undergoing right now
There are also the mutation for lactase persistence and the mutation which allows people in the Andes and Himalayas to have increased oxygen intake at high altitudes.
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You have not demonstrated that. Further, biology is not systematic theology, proof texts do not count.