Male antechinus endure marathon matings that can last up to 14 hours as males compete for multiple partners; the extreme energy and stress can suppress the immune system and cause death after breeding, illustrating a high-risk strategy to pass on genes, while females generally live longer.
Researchers observed a mainland dusky antechinus, a native marsupial in Australia, engaging in cannibalism by eating a dead member of its own species. This behavior was linked to the intense mating period in August, which burns calories and leaves little invertebrate food available. The stress hormone cortisol and surging testosterone during mating cause male antechinuses to die after reproducing, leading to a potential surplus of carcasses for other antechinuses to feed on. This cannibalistic behavior may provide an energy boost for surviving individuals, shedding light on the complex mating and feeding dynamics of these small mammals in the Australian wilderness.