Detecting design or intent in nature

[JuliaL]

If the intellect in question is a natural object, not requiring an intellect for its generation, then its design products are also natural.

By this thinking cars are natural products. When people claim that cars need intellect to exist I think you know very well what they mean.

Unfortunately, I don't.
Are you then saying that
the bowers of bower birds are designs produced by intellect?
the nests of sunfish are designs produced by intellect?
the mounds of termites are designs produced by intellect?

If you say yes to the above, you are giving the termites too much credit unless intellect need not be self aware and its production of 'designed' objects need not be intentional. You're leaning more towards special pleading if you claim that animals only act on instinct while humans produce 'real' design or that the 'designs' produced were in fact inherent in the chain of beings that led from the individuals cited back to the unknown, presumed godlike, first designer.

Evolved intellects are not necessarily designed intellects. We are not discussing intellects being designed or even evolutionary systems themselves being designed. What we are discussing is do evolutionary systems require intellects and it seems that they do.

You asked for an instance of an evolutionary system not intentionally designed by intellect. I considered using the flock, the school or the ant colony. But to be more poignant, I offer religion, arising as an emergent property of human interaction. Among humans, tribes leading to nation states and overall society also qualify. You may object that these involve humans and therefore intellects. The involvement of an intellect in a non-intentional role doesn't count if you are trying to make the inference of a personal God being required to kick off humanity or life on earth. Nobody intended to create the tribe. An impersonal cause is consistent with a naturalistic explanation.