Death After Sex: Israeli Study Finds Male Brown Widow Spiders Prefer Mates That Eat Them

According to an Israeli study, male brown widow spiders prefer to mate with older, less-fertile females who are 50 percent more likely to eat them after sex. Researchers collected samples from central and southern Israel and then gave males the choice of approaching immature or mature females. “We originally thought the males would prefer the sub-adult females, as they are more fertile and far less likely to cannibalize them, but we were surprised to discover that was not the case,” the scientists wrote of their findings in the journal Animal Behaviour. The team subsequently investigated whether the male brown widow spiders had plugged the genital openings of their mates by leaving part of their pedipalps (the male sex organ) inside the females, which would discourage the female from mating again. From a Darwinian standpoint, this would be advantageous for males, but the researchers found no significant evidence of the practice. “One possible explanation is that older females are manipulating the males by using strong signals to attract them,” the researchers concluded, “a hypothesis that remains to be tested.”