Not tonight, deer — picky antelopes ignore pushy exes

SEX with an ex is never a good idea, even when you are a particularly horny species of antelope.

“Not tonight, deer” is the male Topi’s response to persistent advances from former partners, scientists have learned.

The African antelope bucks the normal trend seen among most of its cousins in the wild.

Usually, promiscuous males will mate with as many females as possible while females are choosier about their suitors.

But in the Topi the stereotype is reversed. Popular males find themselves so much in demand they can afford to be picky — and given the choice, they will prefer a new partner over an ex.

Dr Jakob Bro-Jorgensen, from the Zoological Society of London, who led a team of researchers observing Topi behaviour in Kenya’s Masai Mara game reserve, said: “I was interested to see that in cases where the male antelope was free to choose between females, he deliberately went for the most novel mate, rather than the most high-ranking. However, some pushy females were so aggressive in their pursuit of the male he had physically to attack them to rebuff their advances.”

In the traditional breeding or “lekking” grounds of the Topi, the antelope meet for just over one month a year to mate. Individual females are fertile for one day only, when they become desperate for sex. Typically they mate several times with each of about four males.

“The pressure on both the male and the female Topi is just extraordinary,” said Dr Bro-Jorgensen. “The females have just a single day to ensure they become pregnant, and preferably with a hotshot male, so they must focus all of their energies into ensuring that males mate with them in that time.

“The males, however, must focus on maximising the potential of their sperm to ensure they impregnate as many females as possible. It was not uncommon to see males collapsing with exhaustion as the demands of the females got too much for them.”

Competition between females for the most desired males is so great it can result in violence, the researchers reported in the journal Current Biology.

Meanwhile males appear keen to conserve their sperm and not waste it on females they have already mated with.

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