> This raises interesting evolutionary questions. Which came first: colorful signals or the color vision needed to see them?

The question seems to rely on the faulty premise that it is all-or-nothing.

Dawkins explores in Climbing Mount Improbable various examples of complex biological features and shows how they could have evolved step-by-step, with each small change providing some advantage. Examples include the evolution of eyes, the development of flight, spider web construction, and flower patterns.

Eyes have evolved on at least 40 (possibly 65) separate occasions. 96% of animal species have eyes, ranging from simple light-detecting patches to the complex camera eyes of vertebrates and cephalopods.