Human-induced changes in the dynamics of species coexistence: An example with two sister species

This chapter uses long-term studies of the evolutionary ecology of western and mountain bluebirds to demonstrate how human alteration of the density and stability of nest cavities, through the placement of artificial nest boxes, has influenced these species' behaviour, population dynamics and ultimately, their coexistence. It suggests that the fierce competition for nest cavities is a major driver of behavioural evolution. The use of man-made nest boxes is likely to change the density, distribution, and stability of this crucial resource and as a consequence will alter the dynamics of species interactions and possibly the evolution of behavioural and life history traits.