Nothing "in nature" comes about without a need/reason, and I think if we humans hadn't actually needed our intellect the brain/mind would not have evolved.
As someone who has studied biology, I have to correct you here.
I remember my professor asking on the first day of class "what is needed for evolution?"
I said "a need/reason" and he said that wasn't a requirement. After I thought about it (this was years ago) I understood why, and also just how - basic - evolution is.
All evolution is, is mutations combined with the passing on of genetic code. Evolution isn't even "survival of the fittest" (this phrase is a common mistake).
- The copying of DNA isn't perfect. The code isn't copied correctly so that leads to mutations.
- These mutations lead to changes in the organism. That's it. Just changes.
- Sometimes these changes help the organism to survive long enough to reproduce. For these changes to last within the *species*, they must be passed on successfully to a large number of subsequent organisms that manage successfully to also survive until reproduction. It does no good if a single proto-wolf mutates to have sharp claws but its five offspring all die in a flood before they get a chance to reproduce.
- This also illustrates environmental factors. Say a mutation allows a wolf to survive in high CO2 environments. The species lives in a normal CO2 environment so this mutation doesn't help or hinder the species and it gets passed on through completely unrelated circumstances through the generations. Then the area where the species lives gets hit by an unprecedented number of volcanoes and forest fires 500 years later. The members of this species that just happen to have this mutation are able to then survive better until reproduction and so a majority of the population as a whole now have this gene. Shit happened, and the mutation, which happened generations ago now happens to help these organisms. Again, there wasn't a "reason" initially to have this mutation, but because it proved useful at some other point in the species' history, it ended up persisting more overall.
- A lot of times these changes literally do *nothing* when it comes to helping an organism survive until reproduction. They don't help or hinder it, such as a mutation that, say, makes a wolf's claws a tiny, slightly different shade of color. If the organism is good at reproducing otherwise, this slightly different shade of claw color will still get passed onto subsequent generations, and even to the entire species, even though it literally has no survival value and therefore
no "reason" for being there other than there was a copying error during DNA replication and the organisms that had it were good at reproducing for other, completely unrelated, reasons.
- The same can be said for changes that can help the organism or even *hurt* an organism, but not on such a scale that it really determines the organism's chances of surviving until reproduction. A mutation that makes a female wolf get cancer and die after entering menopause will *still get passed on to the species* if the wolves with this gene are otherwise still good at surviving until reproduction. Let that sink in. A mutation that literally
ensures the death of an organism will still be passed on, as long as it doesn't hinder it from reproduction.
- Likewise, a mutation that, say, lets a wolf get really big and strong, but only after it has entered menopause, doesn't help it and the species survive until reproduction, even though it sounds AWESOME and would help the individual organism survive. The ability for this mutation to persist in the species is completely independent of the mutation itself, because it has no bearing on reproduction success.