Quolls pursue an extreme concept of reproduction: After their first successful sex, the males die. Researchers have a theory as to what makes the cute animals so exhausted.
Scientists want to find out why sexual intercourse is a death sentence for male quolls. The cute marsupials from northern Australia are the world’s largest semelparous mammals – meaning males reproduce only once in their lives and then die. This could be due to their unrelenting urge to mate, according to a study published in the journal Royal Society Open Science.
According to the study, because of their sex drive, the males tire themselves out and tire themselves out. During the mating season, they “don’t seem to sleep nearly as much as they should,” said lead author Joshua Gaschk of the University of the Sunshine Coast. This could be a reason for the death of males after mating.
Hoping to shed some light on the mysterious deaths of the males after their first successful sex, the researchers tagged seven male and six female pygmy quolls on the island of Groote Eylandt in tiny backpacks. Data collected over a 42-day period showed that males were significantly more active during the mating season than females, who still live for up to four breeding seasons. While females spent nearly a quarter of their time – 24 percent – resting, males spent just 7 percent.
Smaller relatives such as the broad-footed bag mouse are also semelparous. Research has shown that males die from internal bleeding and infection as a result of the stress of the mating season – but this is clearly not the case with pygmy quolls.
According to Gaschk, the annual death of males could threaten the survival of the pygmy quoll, whose population is already endangered by invasive species such as the cane toad. At the same time, he points out that predatory marsupials have been pursuing the extreme reproductive strategy known as suicidal reproduction for “thousands of years.” “It must have a use.”