It’s the only thing they can do to survive. Sure, it’s not ideal to jump away from your partner after sex. But this arachnid’s life is on the line. The male weaver spider’s dangerous mating makes him reach incredible speeds when jumping. Its scientific name is Philoponella prominens, and knows that if it fails to escape in time, it will be devoured.
Great leap
They use a joint in their first pair of legs that catapults them in a fraction of a second. They reach impressive speeds of up to 88 centimeters per second. “We found that mating always ended with a catapult. So fast that ordinary cameras could not record the details clearly.” Says Shichang Zhang of Hubei University in Wuhan, China. He is the author of the research published this week in Current Biology.
why do they do it? To avoid being devoured by the female in an act of sexual cannibalism. The few males that the researchers saw that did not catapult were quickly captured. Shortly thereafter they were devoured by their mates.
That was discovered while studying sexual selection in this spider. It lives in communal groups of up to 300 individuals in a web complex with many individual webs inside. Out of 155 successful matings, they observed that 152 ended with the male catapulted. All of these air-dropped males survived their sexual encounters.
Swift flight
The three males that were not catapulted were eaten. Another 30 that the researchers prevented from catapulting also ended up in the female’s stomach. Clearly this behavior is necessary to avoid sexual cannibalism.
The dangerous mating of the weaver spider was captured by high-resolution video cameras. An average maximum speed of about 65 cm/s was recorded. Speeds ranged from about 30 cm/s to nearly 90 cm/s. They also accelerated to an average of about 200 m/s squared. As they soar through the air, the males spin about 175 times per second. Unsurpassed circus performers.
“Females can use this behavior to judge the quality of a male during mating,” the scientist notes. “If a male can’t catapult, then kill him. And if a male can perform it several times, then accept his sperm,” he sums up.
