Afrigather Title: Antechinus (Antechinus)
The place it lives: Australia
What it eats: Bugs, spiders, centipedes and generally frogs and small reptiles
Why it is superior: Antechinuses are little marsupials in regards to the measurement of gerbils with a weird reproductive system: the males have intercourse till they die from organ failure.
There are 15 species of Antechinus all with the identical lethal mating system. Their breeding season is a frenzied interval lasting simply two to 3 weeks. Throughout this time, males quit sleep to have as a lot intercourse as doable, going for as much as 14 hours at a time within the hope of passing on their genes. As soon as the breeding season ends, all of the males drop lifeless.
Males die because of stress and exhaustion. Through the mating window, testosterone and the stress hormone cortisol surge of their our bodies. The rise in testosterone prevents them from processing the cortisol, inflicting organ failure and demise.
Some male antechinuses survive, however that is very uncommon. “Males cease making sperm earlier than the mating season and their testes disintegrate, so they aren’t even utilizing vitality on that in the course of the mating interval,” Diana Fisher, a mammal ecologist on the College of Queensland in Australia, stated in an announcement in 2013. “However they will by no means reproduce once more even when they do stay.”
Through the mating season, sperm is saved within the epididymis and is continually misplaced in urine, in order that they have a really temporary window to mate earlier than infertility and demise.
The antechinus mass mortality occasion offers a possibility — contemporary meals for the pregnant females and any males that handle to outlive the sexfest. Females take the chance to cannibalize their very own males.
Associated: These feminine frogs pretend their very own deaths to get out of intercourse
In areas the place completely different species of Antechinus overlap, females can also feast on males from different species. “Every species could profit from consuming lifeless males of the opposite,” Andrew Baker, an ecologist on the Queensland College of Expertise, stated in an announcement in 2024.
Males from one Antechinus species could feed on these from one other if the timing of their breeding seasons permits it. “For the later-breeding species, each sexes could take the chance to cannibalize lifeless males of the earlier-breeding species, to assist stack on weight and situation earlier than their very own breeding interval commences,” Baker stated, including that in a single case, a male — doubtlessly in the midst of his personal mating season — was seen feeding on a “lifeless comrade” had hair loss indicating stress-induced adjustments. “He was maybe destined quickly to develop into any individual else’s meal,” Baker stated.
Gestation in females lasts between 25 and 35 days, after which the undeveloped younger transfer to a pouch on their mom’s stomach to develop for one more 50 days. As soon as the younger are impartial at about three months, the cycle begins once more, with antechinuses reaching sexual maturity at round eight months.
