Consistency in the exhibitions of lekking birds: role of signal repertoire, kinship, and social interactions

Rafael de Oliveira Fratoni, Daniela Malgarini Perez &

Lilian Tonelli Manica

Gestural displays are among the most noteworthy elements of courtship exhibitions in birds. However, while there is increasing interest in the study of avian extravagant courtships, researchers are only starting to explore gestural displays' evolution and there are still significant gaps of knowledge. For instance, a key aspect of such displays is consistency through the ordination of the behavioral elements from the display repertoire.

Here we propose to thoroughly investigate the evolution of bird gestural exhibitions by incorporating display consistency for the first time. We will focus on lekking species, for their exquisite courtship behaviors and unparalleled levels of sexual selection. We aim to test if display consistency is correlated with repertoire across the 16 families of lekking species and in the displays of females in the iconic Pipridae family. We expect that species with simpler displays are more consistent because they are easier to produce. Stronger levels of sexual selection are also expected to favor display consistency. In addition, we will also look at the narrow intraspecific level by focusing on the swallow-tailed manakin (Chiroxiphia caudata), in which males cooperate to produce group gestural displays. We expect that genetic and social affinities favor the consistency of the displays between individuals that cooperate.

By shedding light into a currently ignored but central element of courtship exhibitions in birds, this research will pioneer the study of courtship displays in three ways. First, it will be the most comprehensive macroevolutionary investigation of gestural displays in birds. Second, it will explore the evolution of female displays for the first time. Lastly, it will pioneer the study of kinship and social bonds in signal coordination in manakins.