[AndrewC]

It appears this was a foolish analogy, since clearly fitness does imply more than one specific function.

Well, you didn't read the rest of the discussion, because I answered that. post 53--- Only if the car is not required at the original destination.

[Ichneumon]

[Right Wing Professor wrote:] It appears this was a foolish analogy, since clearly fitness does imply more than one specific function.

[The poster nicknamed Mr. LLLICHY replied:] Well, you didn't read the rest of the discussion, because I answered that. post 53--- Only if the car is not required at the original destination.

I would think that most likely, RWP did read that reply, but rightfully dismissed it as either a missing-the-point non sequitur by the author, or an intentional red herring.

First, stubbornly sticking to the "cars can only go to one destination" aspect of the flawed analogy not only doesn't "answer" RWP's point, it ignores *his* point, which is that fitness involves the fine-tuning of *multiple* functions in an organism, not just one-and-only-one.

Second, the whole "one car on one road" analogy is fundamentally flawed as a model of genetic evolution on several counts, the primary one being that due to gene duplication, genes most certainly *CAN* and *DO* go down "two (or more) roads at once" without having to "abandon" the "original destination" (i.e. current function). And even without gene duplication, a single copy of a gene can perform more than one function, yet again making the "single car" analogy ludicrously unsuitable and grossly misleading as a mental model of genetics and evolution.