Chapter 8 - Mixed-Species Groups

Abstract

Mixed-species groups are typically more than just a chance aggregation of species at the same location. Such groups provide unique costs and benefits. The formation of mixed-species groups extends the theme that animals pay attention to the composition of their groups. In particular, species may pool their specific attributes to increase the detection of resources and predators. Nevertheless, some species may be at a competitive disadvantage in such formations or may suffer proportionately more predation. In general, it has proven remarkably difficult to establish how beneficial mixed-species groups can be relative to simply living with conspecifics. If mixed-species groups have evolved to become functional units with clear advantages to participating species, the formation of mixed-species groups may represent an example of niche construction. Species participating in such groups may have evolved traits in response to novel selection pressures that arose from joining other species. Leadership and mimicry in mixed-species groups represent potential cases of niche construction.