While monogamy in the animal world is not unheard of, frogs have long been considered among the most promiscuous creatures. But, as revealed in a recent study, at least one species of frog mates with the same partner for life--though love, it seems, may not be entirely responsible for this loyalty. A new BBC documentary about these monogamous frogs sheds light into their sex lives, and the secret that helps them stay together for life.
The frogs, Ranitomeya imitator, native to Peru, were discovered to remain monogamous after a series of paternity tests were conducted. The reason for this, as explained in The American Naturalist, has to do with how the frogs raise their offspring.
According to the BBC, after the female lays her eggs on leaf, the male collects the individual tadpoles as they emerge--moving each to its own private reservoir of water that's pooled in the crevices of leaves, high above the forest floor. When the tadpoles get hungry, the male informs his mate, who deposits an unfertilized egg into each pool for her growing young to eat.
This unique cooperation between the male and the female from for the benefit of their offspring, researchers say, is what makes them so inseparable.
Biologist Jason Brown told the BBC:
This is the first discovery of a truly monogamous frog.
Brown and his team performed genetic tests on twelve of these frogs and found that eleven were completely loyal to their partner. Just one frog, a male, was observed 'cheating' on his mate--though it's uncertain whether or not the relationship was 'open'.