Many frog species have bouts of explosive breeding, where males all gather and compete for access to females. In many cases, these competitive exercises are not just energetically costly to males; females can also be killed as many males pile on top of her and all vie for the chance to mate with her. When a female dies, it is a loss of reproductive success not only for the unfortunate female, but also for all of the males who just expended energy fighting to attempt copulation with her. In a small Amazonian frog, Rhinella proboscidea, which is characterized by this type of mating system, these researchers report finding a new reproductive strategy: males fertilize eggs from dead females!
Basically, the males were observed squeezing a dead female’s abdomen in rhythmic movements to extract her eggs. Because the eggs are externally fertilized in this species, the males are able to force a dead female to expel her eggs and can fertilize them afterwards. This functional necrophilia minimizes the risk that females face when entering the breeding pool, because it remains likely that her genes will be passed on to the next generation, even if she dies. And obviously it provides males with more opportunities to mate, and perhaps with less competition to do so.
There are some pretty strange behaviors out there, huh?