The project aims to understand the fitness bases of cooperation in an endemic southern African passerine and the consequences of cooperation for population dynamics through its effects on reproductive output, survival and dispersal. We will continue a unique long-term study of an African bird. We will focus on the evolution of different cooperative behaviours – cooperative breeding, nest building and predator mobbing and on the relationship between cooperation, fitness, dispersal and long-term population dynamics. This is a central theme in biology which of wide interest since cooperation is widespread in nature (including among humans). We will use the exchange of researchers with complementary skills from three European countries and South Africa to accomplish a synergistic collaboration that will overcome the constraints, in terms of skills and funding, of the group members involved. This exchange is expected to have a substantial positive impact on the training of the researchers and students involved and will increase the quality and productivity of the research produced. It is also expected to lead to important networking and long-lasting partnerships between the researchers and participant organisations.