The nature and function of song diversity in southern house wrens (Troglodytes aedon chilensis)

Abstract

This thesis focused on an austral population of House Wrens breeding in the south-temperate zone in Mendoza, Argentina. A description of song organization and complexity is provided for males in this population, and comparisons are made to song patterns reported for House Wrens in the north-temperate zone. Song patterns were remarkably similar between the two zones. Further analyses revealed significant correlations between metrics of song complexity and breeding success in the focal population of House Wrens in Argentina. The latter findings suggest that pressures of sexual selection have affected song evolution in this austral population of House Wrens in ways similar to reported sexually selected effects on song for north-temperate songbird species. This outcome is not well accommodated by current theory. These findings underscore how traditional theory concerning the evolution of song could be expanded through additional studies on South American populations and species, which have been understudied to date.