Following behaviour among Neotropical stream fishes have been scarcely reported. This type of feeding association was observed in a small stream in the upper rio Paraná system between the catfish, Aspidoras fuscoguttatus, acting as a nuclear species, and Knodus moenkhausii, Poecilia reticulata, and Astyanax altiparanae as follower species. Aspidoras fuscoguttatus individuals dug in the bottom d...

The relative contribution of genetic and socio-cultural factors in the shaping of behavior is of fundamental importance to biologists and social scientists, yet it has proven to be extremely difficult to study in a controlled, experimental fashion. Here I describe experiments that examined the strength of genetic and cultural (imitative) factors in determining female mate choice in the guppy, P...

It has been hypothesized that cerebral lateralization can significantly enhance cognition and that this was one of the primary selective forces shaping its wide-spread evolution amongst vertebrate taxa. Here, we tested this hypothesis by examining the link between cerebral lateralization and numerical discrimination. Guppies, Poecilia reticulata, were sorted into left, right and non-lateralized...