Do Self-replicating Motors Exist?

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Do you realize there are variations in the components of olfactory systems spread across many branches of lifeforms that possess them? Do you know that even for us humans, we do not need all the components of our olfactory system to smell things?

The olfactory system in humans consists of many parts like a nose, olfactory bulb, nasal cavity, ethmoid bone, olfactory neurons etcetera, which enable our sense of smell in general. The chain of transmission of olfactory information starts from the nose, through the olfactory nerves and terminates in the olfactory bulb which is part of the brain. This way we get to make sense of the barrage of odorants entering our noses. However, some other lifeforms don’t need all these parts to have functional olfactory systems. Mussels, for example, don’t have noses to pick up odors or a brain to process olfactory signals yet they smell odors like you and I, which allows them to escape predation.

Press article on Mussel study:

Actual paper on Mussel study:

https://www.sciencedirect.com/science/article/abs/pii/S0022098116300545

Moths lack noses as well, but use their antenna to capture scents like pheromones. These examples indicate the answer to the first question (I asked above) is yes, implying that evolution had a suite of parts it could pick from and assemble in different sets of steps to produce the functional olfactory systems we observe in extant organisms. Thus, even if every extant olfactory system was IC, its clear they could have evolved (and they actually evolved).

The second question seeks to investigate if olfactory systems are really IC. Let’s consider the one in humans. Remember our olfaction typically starts in the nose and ends in the olfactory bulb in the brain. If the olfactory system in humans is IC, removing one of its part should completely knockout its function. However, if a person’s nose is removed, they would still be able to smell, albeit with a lot of difficulty, because the nose helps to channel odorants to olfactory receptors located behind the nasal cavity on the olfactory epithelium. This automatically disqualifies the human olfactory system as IC. But there’s more. Its also possible to remove the olfactory bulb itself (which processes olfactory input or smells from the nose) and still retain our sense of smell. This doesn’t hold for everyone though, as some people will largely lose their sense of smell without an olfactory bulb. Interestingly, it seems there are a good number of people (entirely women) with apparently no olfactory bulbs (OBs) whose sense of smell is as good as those without apparent OBs, another strike against the claim of an IC olfactory system in humans.

Press article on people with no apparent OBs:

Actual paper:

https://www.sciencedirect.com/science/article/pii/S0896627319308542

So SCD, next time you claim something is IC, please provide evidence to support that claim.

You are still spouting nonsense. If you are building a PC, the very act of putting a fan into it is functional or useful, because it enables you to reach your end goal, the finished PC. Furthermore, fans or any other PC part are assembled or manufactured first in several steps (which may be functional depending on the intent of the designer), before they are integrated into the PC at different steps.

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i probably agree, but since we have no evidence that even a single complex IC system can evolve in small steps, that argument still hold water and we have no reason to think that such a system can evolve in small steps.

actually i can, but just for some specific objects. notice that i didnt said we can conclude design by looking at any designed objects. im saying that we can conclude design by looking at some specific objects such as motors. see below…

great. now, let’s take it one step further. say that for the sake of the argument that this fan is made of organic components and its able to reproduce (like a living thing). will you still conclude design, or now you will assume that it could evolve by a natural process?:

in addition, can you tell me what was the main reason you conclude design by looking at this fan?

this isnt true for somthing like a watch. right? we all still think that a digital watch need design, and im sure you think so too.

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I will conclude that this is yet another absurd, and thus meaningless, hypothetical.

This horse is long-dead @scd, stop beating it!

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I will then know that it could evolve, since you have now supplied the criteria that make it an evolvable entity. If it is made of mutationally alterable organic polymers that are replicated imperfectly, and the entity is reproducing under natural selection, then yes, it is logically unavoidably evolvable.

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You are the one jumping to a conclusion without evidence. There is overwhelming evidence that evolution is a fact but there is no evidence that a system is IC only conjecture that it is IC.

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Not true. Many systems are irreducibly complex, in that if you remove parts from them they stop working. The problem is this doesn’t mean in any way that they couldn’t evolve. The problem with the concept of IC is that the conclusion to an argument for IC doesn’t follow: Actually IC systems can still evolve. And we know of examples where it happened in real time in the laboratory.

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Thanks for the correction.

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i didnt said that the whole olfactory system is IC. im saying that its IC in general, which means that at least few parts of it are indeed IC. think about a cell-phone: we can take out some parts without dastryong its function. but there are few crucial parts which we cant take out since it will atop function. the same is true for basically any olfactory system. in fact, its also probably true for any olfactory receptor, which needs at least 3 parts: a binding site for the odor molecule, a binding site for a G protein and a part interwoven with the neuron membrane:

so even at the minimal level, we will need at least few parts.

(image from https://www.pnas.org/content/100/6/3035 )

but this is the problem: evolution cant involve a designer, so you need to show how its possible to make that fan, while every step can only be functional inside that PC.

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i dont think so for few reasons. first, there is nothing in a self replicating object that requires it to be functional at all. it can just replicate itself on and on. so not only we need to evolve a self replicating object, but it also need to evolve many functions which are unrelated to replication.

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You define a situation and then ask if the entity could evolve. Since you have given it, in your definition, the attributes known to make something evolvable, it is then evolvable. So now you start blathering about where something self-replicating came from. But it doesn’t matter where it came from, the point is that it now has the attributes YOU YOURSELF defined it to have, and that it is evolvable because it has those attributes.

So now you come up with a new set of attributes you did not previously specify, to try to argue it can’t evolve. Well okay, if you now give it new attributes that prevents it from evolving, then it can’t evolve. You can define whatever attributes you like into the system.

Some systems can evolve, others can’t, and whether they can evolve or not depend on what attributes they have. If you decide to give it unevolvable attributes by definition, then it can’t evolve, obviously.

But there are just no such attributes known in actual living organisms.

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Even if your claim that “we have no evidence that even a single complex IC system can evolve in small steps” was not flat out wrong, the argument would still not hold water.

If we had no examples of IC things that are not made of plastic, it still would not be logically valid to conclude that anything that is IC must be made of plastic. Do you need me to explain why?

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You did. Read your words:

You just said an olfactory system is not IC, now you are saying it’s IC. Confused much?

Furthermore, your definition of IC makes no sense. If I could take away some useful parts from a system and the system still works, then its not IC. Remember the mousetrap: remove the board, it breaks it; remove the spring, it breaks it; remove the clip, it breaks it. Removing one of its functional parts essentially cripples an IC system. This reasoning guided Behe’s first definition of irreducible complexity reproduced below from Darwin’s Black Box, pg 39:

Based on this definition, the olfactory system is not IC, because we can take away several functional parts and it still works.

This is irrelevant. Stick to the topic, the olfactory system (which you incorrectly claimed is IC) not olfactory receptors.

However, it seems you do not realize bringing up an olfactory receptor discredits your claim of the olfactory system being IC. For the purpose of sensing odorants and helping to propagate electrochemical signals to the brain, an olfactory receptor is IC the way you described it: take away the ligand-binding site, it breaks its; take away its G-protein binding site, it breaks it; take away its hydrophobic domains embedded within a nervous membrane, it breaks it. In contrast, taking away some parts of the olfactory system still leave its function intact, disqualifying it as IC.

Evolution doesn’t require every step leading to some biological feature to be functional. Stop knocking down your own strawmen.

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i dont think so. there is nothing in the sequence space for instance, that requires it to be functional. for instance, do you think that there is a sequence which can code for a cell-phone?

do you think that a PC fan is IC, or are you rejecting that idea too?

im saying that a minimal olfactory system is IC. not that every part of any olfactory system is IC.

see above. a part of the olfactory is indeed IC. not the whole system. so i only refer to that part as IC.

so you are suggesting that IC system evolved without natural selection acting on it?

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ackbar

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Actually, yes, a PC fan obviously does not meet Behe’s definition of IC . But that is irrelevant to the point I was making.

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Give an example of this IC minimal olfactory system.

Glad to see you correcting yourself. Olfactory systems like the one humans possess are not IC, but they can contain IC parts. Finally some progress.

Its certainly possible. There is nothing in evolutionary biology that says selection must be present at every step leading to a some feature.

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More than just possible. It has been directly observed under controlled lab conditions.

I must say, it is a bit flabbergasting that @scd has been participating in this group as actively and for as long as he has, and yet has not grasped this fundamental point. The ID Creationists truly are the last True Darwinists.

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although it is not possible to know for sure what the minimum number of parts is (just as it is not possible to say with certainty what is the minimum number of parts for a minimal cell- phone), It can be assumed that at least 2-3 parts are required (and probably more).

so why do you think that no biologist claims that the flagellum evolved by neutral steps? do you realy think that evolutionery biologists can assume that about 30 proteins of the flagellum just evolved without selection till the flagellum evolved?

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In other words you have no evidence for the existence of any minimal IC olfactory system, wherein the removal of any one of its well-matched parts destroys its function. For humans, as we have examined, our olfactory system is not IC and its likely that way for a wide range of organisms that possess an olfactory system.

In addition we can know the minimum number of parts to remain to preserve certain cellphone functions. If I only needed a cellphone to make or receive calls, then I could remove the camera, flashlight and other parts not relevant to that function.

Both questions are based on a strawman you crafted in your head. I never claimed that evolutionary biologists argue that the flagella completely evolved neutrally, rather that not every step leading to the flagella necessarily be selected for or against. Some steps could have been neutral, while others selected for.

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Well there are multiple definitions of IC.

One definition is as you put it. Another distinct definition is “unevolvable”.

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