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In order to build an intelligent design such as a bridge or a mechanical watch, you need a series of non useful steps.

As far as I understand, in random evolution theory, the "intelligence" involved is the process of natural selection.

The problem with this is that natural selection requires that each step be advantageous right away. If I want to build a bridge, I need many steps which would be disadvantageous until the final product which would be advantageous. This would be like trying to write a computer program where each line of code must be advantageous to the program. An intelligent design just cannot be done like this.

How does modern biology deal with this problem? To say it all happened at once, is not possible since the probabilities against this are simply outside the capabilities of a random system. Furthermore even if by some freak monumental event it happened, it would need to happen again many times since there is a huge diversity of intelligent designs in life forms such as lungs in birds vs gills in fish, or sexless reproduction in bacteria versus male/female reproduction in animals (which are fundamentally different).

(Also, as side question has there been ANY experiment demonstrating that such a thing is even possible? I mean for example, to have a computer simulation of random self-replicating molecules, then having an intelligent human being picking out the best version and eliminating the others, then repeating, etc. until you have an intelligent design.)

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The key idea you're missing is that evolution is not random. Read up on "selective pressure". –  MattDMo Mar 30 at 18:26
    
@MattDMo it is random in the sense that there is no intelligence involved. my question is that you cannot build an intelligent design like a mechanical clock without a series of non-advantageous steps. try writing a computer program where each line of code is advantageous to the program. it just doesn't work like that. –  user813801 Mar 30 at 18:55
    
Unfortunately, evolution is not like writing a computer program, which has a very strict syntax, type checking, etc. Please read through the comments and answers to this recent question for a more in-depth discussion. This response in particular addresses the computer analogy. "Advantageous" is a tricky word. There are plenty of instances of DNA changes ("mutations" if you like) that may be negative in the short run, but prove protective otherwise. Sickle-cell anemia is one of those. –  MattDMo Mar 30 at 19:32
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1 Answer 1

What you say is true, but the answer as to how modern evolutionary theory understand this considers other ideas about living things which seem to allow so called 'neutral traits'.

Neutral traits being those phenotypes which seem to have no particular relationship to fitness. Toungue rolling is an often mentioned example. Some folks argue that there is only adaptive changes and phenotype, others like Gould and Lewontin argue that some traits can be the result of pleiotropy.

So first of all this sort of discussion can tell us that the question is argued both ways in a convincing enough way that it is not resolved in biology - some argue quite confidently that all traits are selected for and things like flagellar motors and upright ambulation and eyeballs evolve because of and experiencing constant evolutionary pressure. Others argue that these genes that produce these things are doing something else useful while they are becoming these later more useful traits.

The common twist here is plieotropy. That the genes that are producing the phenotype one is observing is also participating in one or more other biological traits that may is being positively selected for.

A more interesting example of how this works is the domesticated silver fox experiment. Foxes which have had domestication bred into them (just to show that it can be done by selection) lose their red color and their ears are softer and fuzzier. Nobody tried to select for these traits, but they come associated with each fox that is domesticated. Are these traits plieotropic or only very tightly linked? So far they have not been exhibited separately. In any case I think its fair to say that the experiment didn't care about the color of the fox - only its meekness towards people. These traits come along for the ride.

So it might be with any other desirable genetic trait. If a gene becomes closer to producing a lung from a gill, if that gene is sticking around it must be because there is positive selection for that trait, even if the lung like gill is not particularly useful for that fish.

Sorry but I actually disagree that it is obvious that non-useful steps must be had for any such complicated trait. If that were true then you would have a point, but not every biologist would give that to you.

It might be a bit surprising that such discussions are and continue to be matters of faith in science, but I hope you don't dismiss it because of this either. All sciences do assume some things that make their view of the world make more sense. But there are also other components of these theories which are consistently observed and understood that demand them... until they don't.

I don't give really any credence whatsoever when someone says 'this is a widely accepted theory by the scientific community'. This in itself is not a scientific statement, but more the hope that someone else has one somewhere. But a refutation must also take under consideration what is being refuted.

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is there any evidence whatsoever that it is possible to build an intelligent design with this method such as a computer simulation as i wrote in the question. thanks –  user813801 Mar 30 at 6:57
    
traits which arise spontaneously without natural selection cannot explain this, since that would be even worse since then there is no pseudo-intelligence involved. could also be that the foxes change spontaenously as part of their genetic code to adapt to the environment. –  user813801 Mar 30 at 13:04
    
there is a lively conversation going on right here. biology.stackexchange.com/questions/16106/… In my opinion none of this rules out intelligent design - but on the other hand I don't think one can prove there is a Maker by looking at evolution either. that's been consistent with my life experience too... :) –  shigeta Mar 30 at 18:15
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