No, that means that the information content in DNA (an ambiguous and undefined measure) is not highly correlated with the mere number of bases. You don’t have any sort of handle on information or complexity or any similar concept. Now what we do know is that DNA is the means of inheritance; any inherited characteristics must be in DNA, and any characteristics that change in evolution must result from changes in DNA. We also know that closely related, very similar species can differ radically in the sizes of their genomes. Put that together and we find that much of the genomes of many species, humans included, have lots of junk.
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Yes. There’s even a term for this observation:
https://www.cell.com/current-biology/comments/S0960-9822(12)01154-2
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4 posts were split to a new topic: Should Experts Respond to Question From the Public?
Human exceptionalism (cf blue whale, redwood)
I’m sensing an implicit dog’s-ass plot.
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The idea that function=important.
It does ‘something’, therefore vital function!!!
You can say that a grain of sand has a function in producing a beach, and indeed if you had no sand at all you wouldn’t have a beach, but that doesn’t make any individual grain important.
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On the other hand, watching a professional YEC apologist get his ass handed to him day after day on every scientific topic he tries to preach is both gratifying and educational to the lurking public. 
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No, it doesn’t mean that at all. Even if this is the best possible enzyme, the gene that codes for it almost certainly uses some suboptimal codons to code for the amino acids. Which doesn’t make any real-world difference, but try telling that to Sanford.
No, I wasn’t. I agree with that statement. I’m disputing the statement that the vast majority of effectively neutral mutations are deleterious.
I find your analogy of the grain of sand quite interesting in the context of GE. Indeed, imagine a man with a bag on his shoulders has to run a marathon. How would he perform if a grain of sand was put in his bag? How would he perform with 2 grains of sand? With 3? 4? 10? 100? 1000? 10000? 1000000? The same is true for nearly neutral mutations. At the beginning, the few mutations that accumulate in the genome will have no effect on fitness. But at some points, when a certain threshold will be reached, adverse consequences will begin to be felt.
One of the issues that needs to be sorted out is how these get fixed in a population. If you look at alpha actin and sequence it against mammals there is almost a perfect fit of AA positions. If you look at humans alone there are lots of variation from the common sequence.
The mutations are happening and they are deleterious but are not getting fixed in the population.
It is if there are no beneficial mutations at all and the fitness effects are fixed. Neither of which is actually true.
Where in your analogy is the effect of natural selection which is constantly removing grains of sand so overall the runner is unaffected?
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That’s a problem. How could natural selection remove grains of sand when the grains are invisible to selection? If everybody in the race has a similar bag of sand, there’s no selection no matter how much sand is in the bag. There are solutions in population genetics, but simply saying “selection” doesn’t do it.
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Read Giltil’s scenario again. When enough mutations accumulate there is an adverse effect on fitness that is subject to selection.
Yes but the problem is, by this point(this is the idea of GE), they have accumulated basically everywhere. Everyone in the species will have countless of them, littering the genome. Nobody gets born with positive mutations that outweigh all the deleterious ones, they are supposed to be too rare, and the deleterious effects of the “invisible” ones so small that they can accumulate and litter the genome. There are only unhealthy alleles to select among, all of them worse than they used to be, beneficial mutations that truly compensate for them are supposed to be statistically miraculous.
See, this is what correctly laying out an opposing view looks like. And I don’t even feel that i need to also provide a rebuttal.
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My analogy equates the grains of sand with the nearly neutral mutations, ie these mutations invisible to natural selection (in the same way that a grain of sand is « invisible » to the runner).
It’s obvious PDPrice is too busy practicing religious apologetics and has no intention of addressing any the severe problems with the GE hypothesis. We’ll leave it at that.
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The result here depends on whether the relevant selective pressure is from the environment or conspecific competition. If it is the former then selection will act on the cumulative phenotype, those individuals with a fitness below some threshold will not be reproductively viable anymore. If the population reaches equilibrium before extinction, then it stays there, otherwise it goes extinct. Larger populations are more likely to reach equilibrium than smaller ones.
If it is the latter, then selection is always acting relative to the current ‘best’ which changes over time. In this scenario, then fitness will continue dropping unless beneficial mutations occur or fitness effects change, which is effectively the same as beneficial mutations occurring. In either case, populations will again reach equilibrium between new nearly-neutral mutations and newly selectable mutations of either type.
So basically, either the runner collapses (goes extinct) or a hole tears in the bag (equilbrium).
What if a sudden jolt every mile or so spilled out 1 million grains of sand at a time, completely cancelling out the accumulation over that mile?
That would only happen if runners differed significantly in the amount of sand in their bags. If the sand accumulates grain by grain at approximately equal rates among the runners, there is no selection.
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