Social learning in nest-building birds

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In his 'The Philosophy of Birds' Nests (1867) Alfred Russel Wallace wrote: "But, it is objected, birds do not learn to make their nest as man does to build, for all birds will make exactly the same nest as the rest of their species, even if they have never seen one, and it is instinct alone that can enable them to do this. No doubt this would be instinct if it were true, and I simply ask for proof of the fact". With the proposed research I would like to provide the first experimental evidence to support this claim. Specifically, I propose to determine whether birds use information provided by other individuals to learn what nest to build. I would do this via experimentally manipulating the kind of information that is provided by experienced nest-building zebra finches and redpolls to first-time nest builders. In zebra finches it is the male that selects the nesting material and builds the nest while in redpolls, a native British bird, it is the female that both builds the nest and incubates the eggs. Three specific questions I will ask are: what types of information are learned, who do birds learn this information from, and when is it important to learn from other individuals? Different types of information birds could learn from watching experienced individuals build a nest include what type of nest material to select, where that material is located, and how to handle different types of material. Zebra finches and redpolls are both highly social species and in nature, first-time nest builders would have the opportunity to watch multiple nests be built by different individuals, some of which may be more successful (e.g. raise chicks) compared to others (e.g. no chicks). Finally, it is not clear whether once birds have experience building a nest of their own whether they will modify subsequent nests according to what they learn from others, or whether they just rely on their personal experience. By testing two species in the laboratory I can determine the generality of the responses I see, both relative to the sex of the builder and to the specific information provided to the first-time builder from the experienced builder. By coupling those laboratory data with data from birds building in out-door aviaries I can begin to assess the ecological validity of the laboratory results. Finally, this dual-species approach will allow me to exploit fully the data my host laboratory is currently collecting on the neural basis of nest building in zebra finches. For nearly all birds, nest building is the lynchpin to that bird's reproductive success and so it is a vital context in which a builder would benefit enormously from capitalising on the success of others' nest-building experiences. Demonstrating what information is used by these two species when making nest-building decisions is socially learned will begin to address the extent to which social cognition underpins this little-known but fundamental avian behaviour. Given the increasing concern over the flexibility of birds to respond to a changing climate it is timely to ask whether those birds that can recognise and copy the success of some, while avoiding the errors of others, are less vulnerable to environmental changes.