Secret of how tropical spider can turn jumpy after rumpy pumpy
THE prospect of being eaten after sex is enough to make anyone ill at ease. But the male orb-weaving spider Philoponella prominens has turned it into a survival trait, catapulting away from the female with such gusto that cameras struggle to pick up its postcoital exit.
The feat has baffled scientists, but Chinese researchers have now worked out how it is done – with a springy joint in the front legs.
High-resolution cameras showed the spiders, which live in tropical regions of the Americas, Africa, Asia and Australia, fold their tibia-metatarsus joint against the female before releasing it, accelerating at an average speed of 200 metres a second. The few males not seen catapulting were consumed by their partners. Dr Shichang Zhang, of Hubei University, Wuhan, said: “Males that could not perform the catapulting were cannibalised by the female. It suggests that this behaviour evolved to fight against females’ sexual cannibalism.”
Although many animals store elastic energy to escape or catch prey, it is the first time it has been shown in dodging sexual cannibalism. The study suggests the female spiders may even judge their mate’s suitability based on its ability to pull off the move. “If a male could not perform catapulting, then kill it, and if a male could perform it multiple times, then accept its sperm,” said Dr Zhang.
The findings are in