Consider some standard examples of design in nature: the aerodynamic wing of the bird, the concealing coloration of the moth, the dense fur of the polar bear. Darwin's insight was to explain these adaptations as a product of natural selection: individuals vary, some survive and reproduce better than others, and their properties are inherited by their offspring.
All of these adaptations are locally advantageous. Individuals possessing them survive and reproduce better than their immediate neighbors. Now consider some standard examples...
]]>