Male Orb-Weaving Spider Ghosts Female Partner After Sex to Avoid Being Eaten

The tiny species of communal orb-weaving spider Philoponella prominens has to abruptly retreat after mating with a female partner, or it will become its post-sex snack, literally.

P. prominens are social spiders that live in communities - up to 215 - to build connecting webs, according to a study published in the journal Current Biology. However, soon after they mate, they hurl themselves away from their partner as fast as they could to avoid being eaten, Science Alert reports.

While other spider species such as the redback practice sexual cannibalism, this is the first evidence of a spider species using superfast actions to get away from female spiders after fornication to not end up being eaten.

Sexual Cannibalism in Philoponella prominens Male Spiders

Researchers examined 155 successful spider matings in the lab, and found that 152 male spiders were able to "catapult themselves to safety", CNN reported. On the other hand, the other three met an unfortunate "cut-throat fate", as they captured, killed, and consumed by the female.

"Their sensing capability to danger is low, or they have been exhausted during mating, or just could not perform the catapult," said study author Shichang Zhang, an associate professor at Hubei University in China.

When researchers attempted to physically stop the additional 30 male spiders from "catapulting", they, too, fell prey to their partners. "These results clearly indicate that the catapulting behavior is an obligatory component of the male mating repertoire and a strategy to avoid the females' attempts at post-mating sexual cannibalism," the authors wrote.

Using high-resolution, high-speed cameras, researchers show how males of this species escape from their sexual predator by compressing their front legs against the female, then rapidly pushing off to release hydraulic pressure, reaching speeds of up to 34.5 inches per second (88 centimeters per second) to get away. The study also found that both legs were necessary for successful mating.

"I think it is mainly to escape the female, catapulting and spinning make it difficult for the females to catch it," Zhang said, noting that arachnids could also spin up to 469 revolutions per second while leaping away to avoid sexual cannibalism.

Female Spiders Select the Sperm

Going to another perspective, female spiders only select a sperm from a brave heart.

After developing and evolving this "impressive acrobatic escape" of male orb-weaving spider, they will sometimes mate six times with the same female, climbing up, copulating, and bouncing off again until it ejaculates without being killed. Sometimes, he will even lose a few legs in the process. Researchers suspect this is an abseiling strategy of male spiders so their partner will take their sperm, some kind of sexual selection test to assess whether the males are worthy reproductive partners, Zhang said.

"Females may use this behavior to judge the quality of a male during mating," explains animal behaviorist Zhang. "If a male could not perform catapulting, then kill it, and if a male could perform it multiple times, then accept its sperm."

Zhang would like to determine in future research whether there is a correlation between the catapulting ability of a male Philoponella prominens and its ability to reproduce.