Past research
Darwin considered that the difference between human and animal intelligence was a matter of degree, not of kind. Before entering my interdisciplinary journey, my research focused on studying the cognitive ecology and reproductive strategies of dart-poison frogs. I learned outcomes of decision-making in frogs could resemble choices made by "rational" humans. I wonder now about the existence of emotions in frogs and whether they influence their decision-making, as happens with humans.
How to hedge your bets? Breeding site choice in dendrobatid frogs
Among dendrobatids (dart poison frogs), males are the ones taking care of their offspring (except for a subgroup, Oophaga, in which females must feed eggs with unfertilized eggs). After a couple of frogs mate and fertilized eggs lay on the leaflitter, males keep eggs hydrated and, right after tadpoles hatch, transport them to small water bodies (streams, ponds, bromeliads) in which they complete development, turning into tiny froglets.
Parents must be careful at selecting ponds. The smaller the pond, the more ephemeral and the lesser the food and available dissolved oxygen for a tadpole; the bigger the pond, the higher the chances of finding predators that would kill offspring.
My study subject was Epipedobates boulengeri and I worked in Gorgona National Natural Park, Colombia. It turns out dendrobatid males from this species (and presumably females) make pretty sophisticated choices. They discriminate subtle differences among the quality potential of available ponds and hedge their bets by distributing tadpoles among ponds according to the pond quality. Correspondence between pond quality and tadpole distribution was pretty precise when four ponds were available. However, when there are too many ponds, male choices were less accurate. Have you been to a shopping center and tried many clothes? It's easy to lose track of things you were looking at, unless you've found something you really, really liked since the beginning. Perhaps to solve the challenge of making choices, male frogs also use additional information. What better indicative of quality than cues suggesting that other tadpoles were present in a pond? Dendrobatid males use such cues and copy choices made by others males (or tadpoles)!
These froggies are really smart, despite the size of their brain -as small as the head of a pin!
