What adaptive value does the bright color of the upper side of the wings of butterflies have?

The causes of bright color are evolutionary adaptive in nature. All fixtures are the result of natural selection. The upper side of the wings of butterflies is usually brightly and variegated, while the color of the lower side often mimics the color and pattern of the bark or leaves.
The main significance of the bright color of the upper side of the wings is in the recognition of individuals of their species at a great distance. Observations show that males and females of such variegated colored forms are attracted to each other from a distance by color, and near the final recognition by smell occurs.
A bright coloration may also be a warning coloration, such as in a helicoid or mimicry.

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