Tiere: Schwarze-Witwe-Männchen vererben Trick gegen Tod beim Sex

Australian male spiders exhibit a unique behavior to survive mating with a specific type of widow spider known as the "Black Widow" female. This knowledge is passed on to their offspring, according to research from universities in Hamburg, Trier, and Rostock. To study this phenomenon, researchers crossed the Australian Redback spider (Latrodectus hasselti), which performs the trick, with the closely related New Zealand Redia spider (Latrodectus katipo) multiple times.

During sexual reproduction, the Australian Redback males perform a backward jump into the female's venomous fangs, simultaneously narrowing their hindquarters so much that the female's bite becomes less lethal. This increases their chances of survival and allows them to mate with the female a second time.

In contrast, the New Zealand Redia spiders do not perform the backward jump, nor do they suffer the same fate from their male partners. The study co-author Kardelen Özgün Uludağ from the University of Hamburg noted that the different mating behaviors of the two species, which diverged from each other around 100,000 years ago, offer an opportunity to examine the genetic foundations of these behaviors.

The research, published in the journal Biology Letters, involved crossing the New Zealand females with Australian males, then the resulting hybrid females with males from either species, creating males with various genetic combinations from both species. The third generation males, when bred with female Redia from the less dangerous New Zealand species, exhibited the backward jump behavior in nearly half of them, but lacked the narrowing of the hindquarters.

The researchers aim to investigate which specific genes control this unusual behavior and how it has evolved over time.