How the fruit fly got its stink

Drosophila melanogaster (photo credit: André Karwath via Flickr)

Male fruit flies dampen the libido of sexual rivals with smelly pheromone.

The struggle to reproduce and leave behind a genetic legacy has seen the evolution of a variety of weird and wonderful mating features. While male birds such as the peacock don fancy feathers and conduct elaborate courtship dances to outcompete rivals, male fruit flies employ a far less savoury tactic.

For the fruit fly Drosophila melanogaster, the tiny workhorse of the genetics lab, mating isn’t a guarantee of reproductive success. A male who has successfully mated with a female could still be outdone if a rival comes along and mates with his partner after he has wandered off in post-coital bliss. Sperm from both males will compete for the ultimate prize of fertilising the female’s egg.
One way that male fruit flies try to keep their sexual conquests to themselves is by offering their lover a smelly pheromone perfume as a parting gift to repel further would-be suitors.

How this intriguing system evolved is the subject of study published this week in the Proceedings of the National Academy of Sciences, USA. Continue reading “How the fruit fly got its stink”

Not too much perfume, please


Male silkmoths sniff out mates with neurons tuned to detect just the right amount of scent.

Forget elaborate dances, sweet serenades or complicated foreplay. And throw away the Spanish fly and oysters. If you’re a female silkmoth, chances are that your would-be mate is already drunk on your very own elixir of love if he’s within whiffing distance. It takes just 170 molecules of the sex pheromone bombykol to put a male silkmoth in the mood.

Farmers have been using bombykol for years to bamboozle love-sick moths in their fields. But how so few molecules elicit such a strong behavioural response has been somewhat of a mystery to scientists. Continue reading “Not too much perfume, please”