The answer is not quite as straightforward as you might think. Read on to find out about the surprising behaviours and role reversals that redefine the norms of nature when it comes to flies and their mating rituals.
How do flies mate?
In most flies, including the housefly, which buzzes around beneath light-fittings worldwide, the male mounts the female from behind.
In a departure from zoological convention, though, it is the female housefly that penetrates the male, using her egg-laying tube, or ovipositor.
How do crane flies mate?
Another familiar group, the crane flies, tend to face in opposite directions, joined only by the tips of their elongated abdomens.
Where do yellow dung flies mate?
A simple way to witness first-hand the love lives of flies is to get comfy beside a fresh cowpat in summer and watch the sexual antics of the resident yellow dung flies – a source of fascination for zoologists.
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Our experts answer a range of fly-related questions, including why do flies rub their legs together?, why are adult crane flies too busy to eat? and why do flies get into ointments.