The snood functions in both intersexual and intrasexual selection. There are two modes of sexual selection&colon; intersexual selection and intrasexual selection. Both flightless and flying steamer ducks engage in foraging behaviors with interspecific and intersexual differences. Pollinators, like butterflies, show behavioral response(s) to supernormal stimuli through intersexual communication. Sexual coercion often leads to an intersexual coevolutionary arms race. In diving beetle species family Dytiscidae, an intersexual arms race occurs between males and females. Overall, intersexual interaction among common squirrel monkeys greatly increases during the mating season. These implicit biases may underpin common intersexual prejudice&colon; sexism. This selection can be based on intersexual selection, which is selection between two sexes. The peacock's plumage shows intersexual selection, where ornate males compete to be chosen by females. Also, "intersexual selection", or "mate choice", occurs when females choose between male mates. Holmes refers to herself as "still intersexual" after medical intervention. Intersexual selection includes the display of desirable sexual characteristics to attract a potential mate.