A Spider Species Exhibits a Strange Mating Ritual: Male Spiders Shed Female Skin as Part of Courtship.
Scientists in Austria have discovered this eerie behavior for the first time while studying tick spiders, relatives of both spiders and scorpions, in a laboratory setting.
A male spider sheds the skin of a female as part of the mating ritual. (Photo: Peter Schausberger, et al).
The researchers found that males will protect females reproductively once they reach 10 days old and wait until their potential partners begin to molt, according to a study recently published in the journal iScience.
“Males will protect females for several hours,” said co-author Peter Schausberger, a zoologist and professor at the Department of Cognitive Biology at the University of Vienna.
“Males can recognize when females start to molt because their exuviae [the old outer skin] turn silver when air gets trapped between it and the new skin.”
Strangely enough, to help females become ready for mating sooner, males then slide underneath the females and use their foot (a mouthpart resembling a needle) to assist in shedding the skin. After removing the exuviae, the males can insert their reproductive organs into the females.
The researchers also noted that sometimes males will use their two front legs to help females molt, likely to trigger them to start the molting process.
“Mating only takes a few seconds,” Schausberger said. “This protective behavior is energy-intensive and time-consuming, so males want to ensure that no other males can replace them during copulation.”
According to a statement, this dedication ensures a lifelong partner for the males.
Interestingly, the researchers found that sometimes female spiders will “undress” themselves when it is time for them to molt. However, females start shedding from the head, while males shed from the rear first.
Spiders are not the only species that perform disturbing mating rituals in the animal kingdom.
For instance, male butterflies will “penetrate the shell” of a female pupa, a stage in a butterfly’s life cycle after it is a caterpillar and encases itself in a cocoon as a pupa, Schausberger explained.
Schausberger noted that both cases illustrate that fierce mate competition can arise, and these complex behaviors are driven by sexual selection even in the smallest animal species.
