The standard story of the cowboy hat goes something like this: In 1865, J.B. Stetson went out west during the California gold rush. He observed that bowlers, raccoon hats, and sombreros weren't cutting it for men who spent their lives in the harsh conditions of the American West. Stetson went back home and invented "The Boss of the Plains", a waterproof hat with a high dome, ideal for cowboy life. This story would check out if the original Stetson looked anything like a true cowboy hat. Which, with its flat brim, round top, and bow-tied ribbon, it does not.
Johnnie Hughes, author of On the Origin of Teepees, argues that the Stetson's modern form was actually an accident of environment and human habit. The characteristic rolled brim and dented crown are the result of thousands of ranch hands picking up, folding, and sleeping on their hats. The wide brim, waterproof materials, and high crown were responses to a climate with blazing summers and frigid, wet winters. Just like the horse hoof, the cowboy hat was the unintentional result of a population of "organisms" adapting to a grasslands habitat.
It can be problematic to equate natural evolution with the development of manmade objects. Whether or not these changes can be compared to Darwinian selection depends on the intentionality of the design. Some, like corporate logos, superficially appear to evolve like living organisms in gradual, logical steps. However, each iteration of the design can usually be linked back to a conscious decision.
Others are unintentional but non-adaptive. This Boo Berry cereal box, for instance, is more akin to harmless DNA transcription errors than natural selection. Finally, the Stetson hat is a true example of a manmade object that was shaped by actual, unintentional Darwinian selection to arrive at its "fittest" form. Proof that not all design is intelligent.