��è����Ƶs have discovered a gene that, when inactivated, can give flies super sticky powers. The gene, found in vinegar flies and named spidey, after Spider-Man, is responsible for producing their protective waxy coating – switching it off makes flies extra sticky.

The lipids that make up this waxy layer normally act as a raincoat and protect flies against various exterior elements, including microbes and environmental stress. They also carry information about the age, sex and social status of the carrier.

A team of international scientists led by Yin Ning Chiang of the National University of Singapore found that removing the spidey gene caused the flies to lose their protective lipids, resulting in a dramatically shortened lifespan.

“Loss of the lipids allows substances like food to accumulate on the surfaces of their legs,” says Chiang. “The flies eventually get completely stuck to surfaces.”

Without the lipid shield, gunk builds up on the flies. The insects then get caught up in this sticky mess as it aggregates and creates a force that sucks them down onto surfaces.

Attractive coat

Many insects rely on their lipid coating not only for survival but also to choose mates of the right species.

“The discovery of this gene could be a very useful tool,” says Tristram Wyatt of the University of Oxford. “It could help scientists to study the pheromones of fruitflies and further our knowledge of how these chemicals have shaped speciation and evolution.”

The information also could be used for pest control by disrupting insect mating. Because spidey is found in many insect species, researchers think that this finding may prove useful for controlling various disease-bearing insects and agricultural pests through chemical manipulation of the gene to disrupt the animals’ development, lifespan, mating and wall-clinging abilities.

In addition, understanding how the insects’ special lipid raincoat protects them from the outside world could one day help to produce anti-rust, antimicrobial or superhydrophobic surface coatings.

Journal reference: PLOS Genetics, DOI:

Read more: Why insects are the real rulers of the world

Would Black Beauty have made the cut? It turns out mares prefer stallions with deep whinnies. Female horses look for the strongest stallions, but when their view is obscured, they depend on voices to size up potential mates.

In the wild, horses live in harems of adults and juveniles led by a stallion. When the young reach sexual maturity, they usually move to another group to mate. and his team from the University of Rennes 1 in France have shown that, when given the choice, mares go for groups led by stallions with deeper voices – a factor linked with size and fertility.

“Female choice of harem often occurs from afar, where sound is the most effective form of communication for a first encounter,” says Lemasson. So females get a first impression of the stallion based on his concert.

The same authors had previously shown that stallions with deeper voices were larger on average. They have now found that such horses also have a slower heart rate and sire more offspring. By listening to calls, mares might be finding the toughest, calmest and most fertile males – the ones with the potential to be good fathers and protective mates.

How low can you go

The finding could help horse breeders select the best stallions, too. “Breeders will be able to choose the most fertile stallions that excite mares the most so that reproduction happens in an optimal manner,” says Lemasson. “And now all might be able to make that decision based on sound, rather than costly sperm tests.”

Preferring a deep voice is not confined to horses, humans too are subject to the “Barry white” effect. And a similar preference has been recorded in a variety of animals, from deer and bison to giant pandas and koalas.

“In humans, men with lower, more attractive voices also seem to have more attractive faces, and possibly movements and body odours,” says Tamsin Saxton, from Northumbria University, UK. “The cues seem to work together to advertise one’s suitability as a partner.”

But, in humans, there can be too much of a good thing. “Women like deeper voices, but not too low. Too much masculinity might be good for short term relationships but not to build a family,” says Saxton. “And if you try to fake a deeper voice, it might well make you sound more dominant and confident, but probably won’t necessarily lead to people perceiving you as more attractive.”

Journal reference: PLOS One, DOI: