Biparental care in the tadpole-feeding Amazonian treefrog Osteocephalus oophagus

Abstract

The Central Amazonian treefrog Osteocephalus oophagus breeds in water-filled bromeliad or palm tree leaf axils or in treeholes. The larvae feed on eggs provided by their parents; larvae not provided with eggs die. Survival of the larvae is ensured by the fact that the pair always spawns at the same site. They return at intervals of 5 to 7 days. Pair bonding is the rule in areas with low frog densities. The first eggs develop into tadpoles and later clutches of fertilized eggs serve as food. There is no apparent communication system between larvae and mother. After metamorphosis of the larvae the pair continues to lay eggs into the same leaf axils and these eggs also develop into tadpoles. This behavior is compared to that of other frogs that feed their tadpoles on eggs. It seems to be the least advanced mode of parental care involving tadpole feeding and demonstrates one of the initial steps that has led to more complex parental care behaviors in frogs.