DEAD STILL: A male Rhinella proboscidea frog (top) attempts to squeeze mature oocytes from a dead female. COURTESY OF DOMINGOS RODRIGUESFor many frog species, mating is a risky proposition. Males and females gather in veritable orgies that may last days or mere hours. Male frogs can become so desperate to find a mate that a group of writhing males will crush or drown the objects of their desire. But at least one species of Amazonian frog can apparently still produce offspring even if one partner dies in the process. Researchers have observed male Rhinella proboscidea frogs extracting and fertilizing their dead partners’ eggs.
The finding was a surprise, says Henrique Caldeira Costa, a herpetologist at Federal University of Viçosa in Brazil. Other researchers have seen males of various species, from squirrels to penguins, attempting to mate with dead partners, but none “showed a situation where the necrophilia can bring a fitness gain.” Costa and colleagues published a report of a lizard engaging in the phenomenon in Herpetology Notes in 2010.
“Explosive breeding” is a common reproductive strategy among frog species. Males congregate near sources of fresh water and scramble frantically for any females passing by. Only about 5 to 10 percent of males will mate successfully, estimates conservation biologist Marc Sztatecsny, a lecturer at the University of Vienna. “There’s so much competition it makes sense to try to ...
