Ants spend most of the year rearing workers and expanding the number of colony members. In summer, some species begin producing reproductives, male and female ants that have wings. Their nuptial flights occur when environmental conditions are optimal, leading to large swarms of females and much smaller males concentrated on a single day to optimize the chance that males and females from different colonies will interbreed. In Britain, the swarms happen on a yearly basis and are called Flying Ant Day.
Flying Ants Swarm the Cricket Grounds
Photo: Kim Ludbrook/EPA
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