Each year barn swallows dart and swoop in summer skies to catch insects. But these flashy blue and orange aerialists aren’t on the hunt for only food. As is true with our own species, barn swallows use athletics and appearance to show off to the opposite sex.
With their distinctive forked tails, barn swallows are widespread. On multiple continents they build mud cup nests under bridges and in barns and other human structures. But their choice of mates varies from place to place.