Mother Poison Dart Frogs Supply Their Tadpoles With Poison.

In a recent study, Styonski and colleagues examined strawberry poison dart frog tadpoles, juveniles, and adults to identify when the frogs acquire the deadly alkaloids that so successfully ward off predators.

The maternal role in strawberry poison dart frog reproduction is highly significant. In order to place each tadpole in a pool of water well above the forest floor, adult females would carry their young on their backs to bromeliads (plants related to pineapples that thrive in the canopy of tropical forests). Each tadpole needs to have its own pool; else, they will eat one another. The mother goes back to each pool and places a fertilized egg once all the tadpoles from a brood have been separated and placed in individual pools. This egg provides nutrition for the tadpole as it grows. This procedure lasts from one to five days.

Adult strawberry poison dart frogs typically obtain their venom from their diet of ants and mites. However, it makes natural that these tadpoles would be helpless given that they are only eating what their mothers offer them. But this is not the case. According to Styoski's research, Oophaga pumilio tadpoles receive their alkaloids from their mothers' unfertilized eggs as they grow. Juveniles have a higher potency than tadpoles but not as much as adults when they mature into the juvenile stage due to the initial accumulation of alkaloids provided by their mother and additional alkaloids supplemented by their food.