Should it find the eggs, it will gobble them up like so much tapioca. These may belong to species of Leptodactylids that have left streams altogether and chosen to take up residence in small burrows excavated by the male. Before the rains come he calls to attract a female and, if successful, mates with her in the burrow. Using his back legs he whips up a foam from air, water and mucus as he rides on her back. Into this the eggs are laid, ensuring that they will remain moist underground.
Tadpoles develop protected by the foam and, when the rains come, the burrow fills.
Soon young froglets emerge to paddle out into the forest. Another genus of Neotropical frogs, Eleutherodactylus , has gone one stage further. When the tadpoles are ready to hatch, the female searches out a suitable bromeliad up in the canopy and crawls down into it. There the young tadpoles wriggle from her back and into their pool in the trees. Those in the genus Gastrotheca retain their eggs in their pouch right through the tadpole stage, a wriggling mass under their skin flap.