During the breeding season, red deer stags spend most of their time roaring. It used to be thought that roaring was simply a kind of ritual fighting, a contest to see who is stronger. But a stag with a harem roars much more than he needs to if intimidating the opposition is the only aim. He’ll typically roar at least twice a minute all day and all night. Small wonder than after a couple of weeks he’s exhausted. It’s worth it though. For females, roars are an aphrodisiac: females exposed to vigorous roaring come into heat sooner than females who are not, and females who conceive earlier in the breeding season give birth earlier the following spring and are more likely to have their calves survive. By the way, male red deer masturbate by rubbing the tips of their antlers through the grass. The whole act takes 15 seconds from start to spurt, and during the breeding season some stags masturbate several times a day.

Text adapted in part from Dr Tatiana’s Sex Advice to All Creation