Boffins have been surprised to discover that a species of poisonous frog remain utterly faithful to one partner.
Apparently this brings us closer to understanding why human society places such store on remaining faithful to just one partner.
According to the journal The American Naturalist, which we accidentally bought thinking it was something else, the monogamous frog species Ranitomeya Imitatoris is devoted to its kids and partner.
Dr Jason Brown of Duke University said it was the first discovery of a truly monogamous amphibian.
After mating, a female mimic poison frog lays her eggs on the surface of leaves. The male frog then takes away the tadpoles that hatch, carrying them one by one on his back to pools of water which collect in bromeliad leaves high up in the branches of trees.
The female partner feeds the tadpoles with a non-fertile egg in each pool, which the tadpole eats as food.
The male and female frogs appear to act together and do not, as some animals do, shag, raise off-spring and then look for another shag.
By sampling the the DNA of many pairs of adult frogs, Boffins have found that they tend to stay together. This makes the Ranitomeya imitatoris the first confirmed monogamous amphibian. Its closest genetic relative apparently is choosey, so why Ranitomeya Imitatoris is so loyal seems to be because of the need to protect tadpoles. Also the fact that the males are responsible for raising the "kids".
Projected onto a human society a couple that has children and a mother going to work leaves a house husband to raise the spawn means they are more likely to stay together than bed hop. Of course a lack of a decent internet connection might help frogs from straying. [That's enough frog spawn, Ed.]