A spider with a 'catapult-type escape mechanism' that escapes at super high speed because it cannot be eaten by females after mating
sexual cannibalism ' in which females eat males after mating. A newly published paper found that a male spider, the pine spider, has a mechanism for fast escape from females after mating.
Spiders and praying mantis are known to perform '
Male spiders avoid sexual cannibalism with a catapult mechanism: Current Biology
These male spiders catapult at impressive speeds to flee their mates before they get eaten
These male spiders use built-in leg catapults to escape sexual cannibalism | Live Science
These male spiders catapult away to avoid sexual cannibalism | Science News
Shichang Zhang and his team, who are studying biology at Hubei University in Wuhan, China, wrote in a paper published in the academic journal Current Biology on April 25, 2022 that male Matsugaeuzu spiders were from females. Announced that it has a catapult-like structure on its legs to escape.
You can see how a male Matsugaeuzu spider escapes from predation by a female in the video below.
How a male spider escapes becoming its mate's lunch | Science News --YouTube
This is an image of a male Matsugaeuzu spider escaping from a mating female with an ultra-high-speed camera. Of the two, the orange one above is the male.
A male who senses cannibalism changes his posture.
The next moment, the male jumped, stretching all the legs he was using to attach to the female's body.
It's so quick that you can only see afterimages in images taken with a normal camera and you can't tell what's going on.
According to the research team, the speed of 'catapult behavior' that ejects itself after mating has reached a maximum of 88 meters per second. This is the speed equivalent to a human adult jumping 530 meters in a second. Regarding the mechanism of this catapult, the research team explained, 'There is a hypothesis that the leg is folded against the female and the pressure is released instantly to extend the leg.'
There are other creatures with structures that use elastic energy, such as mantis shrimp that shoot powerful punches and jaw ants that jump with jaws such as leg-hold traps, but all of them are when catching prey or conversely when escaping from predators. It is used for. It is the first time that the Matsugaeuzu spider has been confirmed to use this structure to escape sexual cannibalism by females of the same family.
To investigate the frequency and importance of this 'catapult behavior,' the research team observed 155 matings of the pineapple spider. As a result, it was confirmed that 'catapult behavior' was performed 152 times, which is 97.4%, and that males survived in all cases. However, all three males who did not perform catapult behavior were preyed on by females. The same was true of the fate of the 30 males, who prevented researchers from performing 'catapult behavior' by brushing their backs.
'It has been suggested that this behavior has evolved to counter sexual cannibalism under strong predatory pressure by females. Perhaps females have the quality of males in this catapult behavior,' Zhang said in a statement. If the male can escape successfully, he will accept the cannibalism as many times as he wants, and the male who cannot escape will be killed. '