Do woodpecker nches acquire tool use by social learning

Tool-use is widespread among animals, but except in primates the development of this behaviour is poorly known. Here, we report on the ¢rst experimental study to our knowledge of the mechanisms underlying the acquisition of tool-use in a bird species. The woodpecker ¢nch Cactospiza pallida, endemic to the Galäpagos Islands, is a famous textbook example of tool-use in animals. This species uses modi¢ed twigs or cactus spines to pry arthropods out of tree holes. Using nestlings and adult birds from the ¢eld, we tested experimentally whether woodpecker ¢nches learn tool-use socially.We show that social learning is not essential for the development of tool-use: all juveniles developed tool-use regardless of whether or not they had a tool-using model. However, we found that not all adult woodpecker ¢nches used tools in our experiments. These non-tool-using individuals also did not learn this task by observing tool-using conspeci¢cs. Our results suggest that tool-use behaviour depends on a very speci¢c learning dispositio