The social dynamics of cultural behaviour: transmission biases and adaptive social learning strategies in wild great tits.

All animals need to make the most of new opportunities or deal with changing environmental conditions. These changes may be short-term such as seasonal change, or long-term shifts such as climate change, and often impact the availability of food resources and, potentially, survival. Broadly, two different strategies might be used to increase access to resources in a changing environment. Animals might develop new solutions to problems (innovation), and thus find new resources themselves, or they might observe others and copy successful solutions. The latter, called social learning, is expected to be much more frequent than innovation, allows new behaviours to spread rapidly between individuals and is thought to be fundamental in forming traditions. Social learning has long fascinated biologists and anthropologists; understanding how behaviours spread and traditions are maintained in animals can shed light on the factors promoting complex culture in humans. An important determinant of social learning is the social organisation of the population in which learning occurs. It was long thought that only humans could exhibit highly developed cultural transmission due to their capacity for communication and learning that is facilitated by long-term social bonds. However recent research has found locally maintained cultural behaviour in a wide range of animals. Further, social network analysis in both human and other animal populations has allowed population structure to be accurately measured. Thus, using social networks to map the spread of new behaviours provides an exciting opportunity to understand this important learning process. In this study, we will study the spread of novel information in wild populations of a common bird, the great tit. All individuals in our large study population are tagged with microchips allowing us to track them automatically; our pilot data shows that they will learn socially. We will develop devices where one of two simple solutions provides access to food, and train an individual to solve one solution on the task in captivity before releasing it back into the woodland where we will place a number of these devices. Using this approach, we will be able to track who has learnt, from whom they learnt, and which of the two solutions they learnt. Using the social network of this population, we will track the spread of the new behaviours, and determine what characteristics made some individuals more important in spreading them. By training different individuals on the two different solutions, we will also see how local traditions develop and are maintained. Not all traditions or behaviours are advantageous. For example, in humans it has been shown that obesity can spread through friendship groups. In the second phase of this project we will alter the reward to different solutions of the task by replacing the popular solution with a low reward (peanut granules instead of a worm), maintaining the high reward on the less popular solution. This will test whether bad traditions are maintained through social reinforcement where individuals blindly copy the majority even when better solutions exist. Finally, we will develop some new technology that will predict what solution new individuals should be learning based upon the behavior of the group they belong to. By changing the behaviour at the device in response, we will then test in detail what elements of the behaviour observed in others is used when social learning. This will be the first time that anyone has used an active device to directly manipulate the behaviour of wild animals in this way. This will itself advance scientists' abilities to understand what rules individuals follow when making decisions such as who to copy and when. Such knowledge will be widely applicable across disciplines, for example in providing new opportunities for active conservation of threatened species by introducing behaviours that improve survival.