Mosquito: Most animal mating rituals involve a guy trying to impress a girl. Leave it to the lowly mosquito to rescue equality among the sexes: their song. Though the male’s wings typically produce a sound with a frequency of 600 hertz, and the female’s wings a 400 hertz song, each mating individual will adjust his her or sound so as to meet in the middle. The resulting harmonic convergence is, at 1200 hertz, a bit like love itself: more than the sum of its parts.

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