Let me say that I think that evolution indeed occur(ed).
But the concepts of "adaptation", "environmental/reproductive pressure" have poor cognitive significance (even if they were properly defined, which is not the case) or are simply false/meaningless.
I also repeat that I'm an Agnostic and don't believe in God, therefore I don't believe in the ID 'theory'.
Still, I think that the NS ‘theory’ is more mystic than scientific… It seems to defend the idea that "Nature" (in opposition to humans or choice) is guiding the selective process, therefore evolution… Replace the word "Nature" by "God" and see what you obtain…
Also, please note that the questions I ask or the comments I make do NOT necessarily represent my position on the matter. I often use them to play the role of the Devil’s advocate.
For now, I will simply respond to the comments made on my last post.
I also want to say that I agree with some arguments made by Maleagar, the main ones being:
"I hardly think that the existence of extra-genomic system processes that interact with the environment, thus changing how coded sequences from the genome are interpreted, and what meta-system must exist which runs that system, [describing when and how to read sequences forward or backward, or when to change the formal order]" --this part, not being an expert, I‘m not sure about-- "can be considered "irrelevant". Such meta-interpretive extra-genomic systems increase the combinatorial problem faced by "random mutation" theorists. "
Regarding the Baldwin effect and epi-genetics.
(1) How do scientists establish that the mutations are in fact (or at least, in principle) random?
(2) How do scientists establish that the different genomic sequences in fact (or at least, in principle) are the sufficient and necessary causation of the major taxonomic variances?
(3) How do scientists establish that the selection methodology for taxonomic success is in fact (or at least in principle) natural, and not artificial?"
For the 3rd one, I’ll differ a bit by asking what is the definition of ‘natural’ in this context? Is it simply a negative definition: Non-artificial, non-human guided? Or is it Guided by ‘Nature‘? If so, define ‘Nature’ please.
Also, can the potential action of the organism carrier transmitting the gene(s) be considered as ‘natural’? Is it considered at all? (I’ll develop on these two questions below.)
Your arguments have become very weak after the intervention(s) of Maleagar...
If there is a "reshuffling" (random), it still doesn't provide a cause for the mechanism called "environmental/reprodutive pressure".
1. I bring up "environmental/reproductive pressure" because it's an essential part (conclusions C1-3, C2-4 and C3-4 use the concept of "pressure") of Alun's demonstration (the reason for this thread to exist) and of the validity and soundness of the theory of Natural Selection (guiding adaptation and evolution).Wowbagger wrote:Why do you bring up environmental/reproductive pressure?
These terms together are part of natural selection, which, combined with mutations, leads to adaptation (evolution).
Organisms have more offspring than needed to keep their numbers constant. Offspring varies genetically. Resources are limited, thus, it comes to competition. Because of the developing 'environmental/reproductive' pressure, on average, the better equipped organisms tend to survive.
2. "These terms are not combined with mutations", they precisely are said to explain mutations.
So, thank you but I know mutations lead to evolution, but my questions still are: "What causes these mutations to happen?" What is the definition of environmental/reproductive pressure? E.g. What mechanism(s) is described by these concepts?
You cite some causes for mutations to happen (gene transfer, viral/toxin insertions/assimilations and cosmic rays, let's put genetic engineering aside as it's not a "natural" process) but they don't explain all mutations, by far.
Meleagar mentioned the concept of "epigenetic" and even if anything non-genetic can be qualified as epigenetic, it raises an interesting question as it means that geneticists seem to know they have yet to identify other causes...
So, why keep on asserting that randomness is "guiding" NS, thus adaptation?
There is a problem of level of understanding here. At a genetic level, causes like gene transfer, viral/toxin insertions/assimilations and cosmic rays appear to occur randomly.
In fact this is not randomness but clearly what is called "unpredictability" (it doesn‘t mean unpredictable by nature, but currently unpredictable due to the complexity and number of factors that exist as causes and are being able to influence the outcome of a process), which is different.
Example of your misunderstanding:
Wowbagger wrote:So, you see there are causes. Their occurrence cannot be random then.
They are not predicted due to our current knowlege of such causes, but they are NOT unpredictable by nature though.
It is very relevant to know if determinism apply or not. You're confusing randomness (absence of causation inherent to the nature of the studied system. See Quantum Mechanics.) with unpredictability (a system too complex --for now-- to theorize the outcomes of initial events/conditions… See Chaos Theory.).Yeah, that's what I said. Like throwing a dice, you can't predict the outcome, but of course, it is somehow determined, or, if determinism doesn't apply (doesn't matter for that discussion), at least caused to fall a certain way. It still makes sense to call it 'random' though, as opposed to 'guided', we just have to agree on what is meant.
BUT, as these are CAUSES (for mutations to occur), there is NO RANDOMNESS. Randomness is NOT THE CAUSE for mutations to happen. Still, we have yet to identify them all (even if scientists seem to be satisfied with the ones they have).
So, what does it mean when the scientific community asserts that genetic mutations occur randomly?
Well, it's a lie. Pure and simple.
The cause for their occurrence is unpredictable, not random by nature.
And what about the causes for genetic mutations themselves? Geneticists are quite embarrassed as they identified some objective causes they cannot deny to exist.
Again, so much for randomness...
But they still try to invoke (like occultists would do for a supernatural entity) a vague mechanism there is no definition for (it's not at all or partially explained but omitting a number of possibilities potentially explaining mutations) called environmental and/or reproductive pressure to hide their embarrassment.
This is supposed to be the inference/link between Mutations, NS and adaptation/evolution.
Environmental pressure à Mutation à Reproductive pressure à NS à Adaptation/Evolution
Two mechanisms (environmental and reproductive pressure) yet to be defined and even yet to be considered as mechanisms… Fantastic…
But if they simply get rid of the supposed random cause (not the random/unpredictable occurrence of these causes. You understand the difference?) and try to find or recognize that they haven't identified all possible causes (some humility, maybe?), we could have a sane, healthy discussion about the causes for genetic mutations and what really mean "adaptation" and "Natural Selection".
If we can't even consider the environmental/reproductive pressure to be a mechanism (yet to be meaningfully explained though), how can we identify the cause(s) for (mechanisms that induce) environmental/reproductive pressure itself?
It lacks inferences in Alun's demonstration for these very reasons... That's why he answers "there is no evidence for the existence of such mechanism", and see no problem with it...
Wowbagger wrote:1- It doesn't suffice to claim the causes of genetic mutation may be due to cosmic rays, one has to PROVE it to make it a scientific hypothesis.
Better, one has to prove and identify ALL the causes and verify if they explain ALL mutations ("naturally") occurring.
What Ockam's razor has to do with anything here. I don't make allusion to any entity.Ockham's razor.
I simply ask for an empirical proof. Not only that cosmic rays may induce mutations but that they actually explain some.
Isn't how science is supposed to work?
A claim must be backed up with proof. Not by the mere possibility that a proof may exist.
And to do that not only with cosmic rays but for ALL (identified and yet to be identified) causes for such mutations to occur.
If not, it's an incomplete hypothesis at best, the result of divination at worst... Since probabilities and statistics don't give any cause for a phenomenon/event to happen.
Direct action of the environment?
Yes direct action, like cosmic rays could have. They would have a direct effect (IF they had one) on the genome of the individual expose to , it causing mutations to happen.
So, direct causes can exist and be identified. Any cause that hasn’t a proven direct effect on the genome is not a cause, nor a mechanism. It’s unscientific to claim their role!
P1-3) If an organism does not reproduce itself, it will eventually die and its genetic information will not be expressed.
* I think this follows deductively.
C1-3) If a mutation does not help an organism reproduce, there will not be any pressure for that change in genetic information to promulgate.
* This is microevolution by natural selection. We see it all the time in antibiotic-resistant bacteria.
P1-4) Reproduction itself is governed by the expression of DNA.
P2-4) Two populations of organisms that do not reproduce using one another's genetic material are of different species.
C1-4) Species can diverge due to the accumulation of gradual mutations.
* This has been explored on a genetic level for past eukaryotic species divergence events .
* This has been observed in the present tense for bacteria .
C2-4) Species can diverge due to reproductive pressure (from C1-3).
* This has been specifically observed in the present tense in many types of organism .
* This is the theory of evolution by natural selection.
Inferring using this with respect to the fossil record, we can further say:
C3-4) Evolution in the past can be explained as a consequence of species divergence due to reproductive pressure.
As you don’t seem to understand the problems with your demonstration. Let me go further.
The form of your demonstration:
P1-3) If an organism does not reproduce itself (P1-3a), it will eventually die (P1-3b) and its genetic information will not be expressed (P1-3c) .
Premises and conclusions cannot be formulated using conditional(s). Your use of the preposition "if" is then incorrect.
The form of your premises (here P1-3) is also incorrect as you start the first proposition with a conditional ("if"), and then make a conclusion in your premise based on this conditional.
That’s an incorrect way to present a premise. From one part of your premise (P1-3a) you seem to deduce a second proposition (P1-3b) and then a third (P1-3c), so it’s de facto two conclusions you deduce from only one premise (P1-3a) and that is not explained with any inference.
Therefore P1-3 is an invalid "premise".
You should at least make 3 premises of P1-3, without conditional.
C1-3) If a mutation does not help an organism reproduce (C1-3a), there will not be any pressure for that change in genetic information to promulgate. (C1-3b)
Again, conditional and here a split-in-two ‘sub-conclusions’ with what should be a premise (C1-3a) and a conclusion (C1-3b).
You deduce this conclusion from only one premise, also incorrect.
You arrive to this conclusion without giving any inference (I think this follows deductively is not an inference/explanation.). And, there is no causation between P1-3 and C1-3.
So, C1-3 is invalid and unsound.
C1-4 (Species can diverge due to the accumulation of gradual mutations) cannot be deduce from P1-4 and P2-4. Also, it presents two concepts (divergence and gradual mutations which are cited for the first time without having been linked to the previous demonstration)
Therefore, your conclusion is invalid.
P1-4, P2-4 and C1-4 may be true (sound) but there is a lack of causation between these two premises, the concepts of divergence and gradual mutations, and (the statement made by) your conclusion. Your demonstration lacks of, at least, two (necessary) premises evoking gradual mutation and allowing to make a ’connection’ between P1-4, P2-4 and C1-4 and at least one inference (explaining how gradual mutations cause divergence).
C2-4 cannot be deduced from P1-4, P2-4 and C1-3 as C1-3 is invalid and unsound.
Same for C3-4.
Now, let’s evaluate the content of these "premises" and "conclusions".
P1-3: You seem to confuse the individual organism with a (sub)species of organisms . An organism (beside xxxxx) rarely reproduce itself. Plants, animals and us, humans, surely don’t.
C1-3: Do you tell me that the concept of (environmental and/or reproductive) "pressure" only means: not more likely to survive??
Pressure, definition: "not more likely to survive." It’s nonsense Alun. Why this concept even exist then?
So, C1-3 would become: "If a mutation does not help an organism reproducing, it will not be more likely to survive and that change in genetic information will be less likely to promulgate."
It isn’t much of a conclusion, Alun.
Also P1-3 and C1-3 seem to mean almost the same thing, they have the same cognitive content/significance.
It should take the form of something like this:
P1: Individuals among a given species reproduce with one another.
P2: Mutations occur among (the genome of) species.
P3: Mutations are divided in 3 kinds: impairing (I think it is a more precise term than non-beneficial as neutral mutations can be considered as non beneficial but can‘t be seen as beneficial), beneficial, neutral.
Inference: As impairing mutations induce dysfunctions of the body/organs/cells, unaesthetic changes… Carriers of these mutations are less likely to survive till the age of reproduction or to be able to find a (willing) mate to reproduce if they attain this age.
C1: Impairing mutations are less likely to allow reproduction.
C2: Beneficial mutations are more likely to allow reproduction.
(Cn: Neutral mutations are neither more nor less likely to allow reproduction. We are not interested in these, here.)
These two proven, sound and valid conclusions can now be used as premises:
P4: Impairing mutations are less likely to allow reproduction.
P5: Beneficial mutations are more likely to allow reproduction.
Inference: The genome and mutations of the dead or unfit individuals are less likely to be transmitted.
C3: Impairing mutations are less likely to subsist.
C4: Beneficial mutations are more likely to subsist: "Subspecies" are created which can reproduce with all members of the studied species and become the new ‘dominant’ (sub)species.
The term "subspecies" is not the proper one to use, but I don’t have the right one in mind.
Note that there is no certainty for the elimination of impairing mutations, they still can survive for a time, depending on the level of ‘unfitness’ (not relatively to their environment but to the efficiency of their own body) resulting from these mutations. They can also stay dormant much longer.
Neither there is certainty for the beneficial mutations to subsist... One could argue that there is a statistic certainty that they WILL disappear (given enough time)… Well… Statistics…
An impairing mutation can also become beneficial if the environment change and render this mutation beneficial by making the carrier more adapted to this change.
More, my classical logic "demonstration" doesn’t account for the causes of these mutations. It still is needed.
I make no allusion to "pressure", nor adaptation. There is NS though.
If you want to include environmental direct action through cosmic rays, assimilation of toxins, appearance of new predators, change in the climate or biotope… (no "pressure" which is an empty concept) or epigenetic factors in the process of genetic mutation, NS and adaptation… You have more work to do.
All this to show that we don’t learn much from this demonstration… And that your C1-3 is still invalid and unsound (false and not supported by facts). (reproductive) "Pressure" means nothing.
C1-4 and C2-4:
First, you’re confusing, fail to differentiate 2 epistemic/cognitive levels here.
The divergence due to reproductive pressure is (considered as) the CAUSE for the divergence due to accumulation of gradual mutations.
Also and again, were do "divergence" and "accumulation of gradual mutations" come from?
I mean they are formulated in a conclusion so they should have been presented, explained and proved before, right? They haven’t.
You still don’t even explain what "reproductive pressure" is, nor from what demonstration you come to the conclusion of its existence, role and nature.
So, C1-4 may be sound (true) but you give no demonstration other than saying "This has been specifically observed in the present tense in many types of organism".
C2-4 is unsound, undemonstrated and invalid, so it’s false and "This is the theory of evolution by natural selection." Is a meaningless, unfounded claim.
C3-4: Well, I won’t repeat the same arguments. I think you understand.
Now, I want to point out that everyone is forgetting or doesn't see a third potential candidate (the first is "environment", the second would be a God/Designer -- whom I don't believe in --) which could ‘guide’ these genetic mutations, therefore adaptation: the organim itself!
Let's take the example of the island, as it's an easy one.
Rats tend to become bigger (gigantism) on islands, it seems logical since the bigger rats have a competitive edge on the smaller ones, even and above all when it comes to reproduction as it often entails violence between ‘suitors’ to a female.
Other animals (like horses) tend to get smaller (dwarfism) because, for example, of the lack of resources and of space.
But it doesn’t explain why these types of mutations happen more frequently or only on islands.
Why gigantism is beneficial only on islands?? Why all rats don’t become bigger. The advantages would be the same everywhere…
Then, what about birds that loose their wings, what is the objective adaptive advantage a wingless bird has over a "normal" bird?? Wings or not, it needs approximately the same amount of food. Wings would even seem to be an advantage for obtaining food, by reaching places a wingless ‘bird’ could not... Also, a "normal" bird can escape predators more easily.
What about the reproductive edge then? A bird with wings should appear more attractive, healthy... to a female as it is the norm when birds with smaller and smaller wings appear.
What about the claim that evolution can "never go down on Mount Improbable" (Dawkins)?
It would seem that adaptation (to a new environment, here an island far from any coast) can not only distance itself from the "competitive/reproductive benefit/advantage" hypothesis but act against it, against the NS theory!
Could that be because the bird, understanding the uselessness of its wings, unconsciously decide to repress the combination of genes that would give him fully operational wings? (Not taking all factors in consideration of course.)
I know... That would mean they not only have a consciousness but also a subconscious like humans do.
But it's not even the most surprising, interesting, mind blowing possibility...
It would mean that animals (all organisms, us included?) can un-consciously interfere in the mutation process by modifying their own (active) genome.
I know it's pure speculation, but a logical one.
Why assume/accept for a fact that the cause for mutations (and what we call "adaptation") can exclusively be "randomness" (no cause at all which is anti-scientific and illogical) or "guided" by extrinsic factors (environment/Nature or God)??
I know the consequences of such hypothesis (if proven true or even possible through observations, experiments and/or the use of the scientific method) are tremendous. Is it why no hypothesis of the sort has been formulated yet?
It is not so far fetched as we KNOW our brains regulate ALL our body activity at a neurological subconscious level. What are the logical implications of this fact? Well, I let you think about it...
Or how come organisms get rid of simply unnecessary features?
We're not talking of impairing ones for a new environment (neither neutral ones), only unnecessary ones (also like the sight of animals living below the surface in caves. Why not improving the night vision instead of having no sight at all?). Do organisms develop new ones to compensate (like ultrasound)? If so, can they be un-adapted for thousands, millions of years in the meantime? Then, why stay in non-fitting environment when they are clearly not suited for them and they can change of such environment?