Sometimes something unused is a natural consequence of implementing something useful. However a large intestine comes to be, the appendix may very well be an unavoidable result.
Sometimes something we think unused actually has an active purpose we just don’t understand yet. Turns out the appendix does have a purpose after all, we just didn’t grasp why until recently.
And sometimes something may evolve by chance, not beneficial but not detrimental either, having no reason to be de-selected out of existence.
Too much of ID argumentation amounts to “I don’t see why/how X exists, therefore it’s wrong/nonexistent”. Too much insistence on having perfect knowledge on both sides, too little humility that 2.5 pounds of wet brain cells just a few decades old is not well suited to understanding billions of light-years of content.
Im not arguing ID over evolution via natural selection..I’m arguing inside the theory of evolution via natural selection..
natural selection cannot favor or if you will select something that is not functional or or used...
you bring up things like colon or appendix which are things that had function in the past so at one point could be naturally selected in the past but now are obsolete ...
that’s fundamentally different than something that has never been used the only way we could have excess capacity of the brain is that at some point in the past it was necessary and used to be selected to be included in our genetic makeup
at least per the logic of natural selection.