Differences in plumage coloration predict female but not male territorial responses in three antbird sister species pairs

Celebrating the Great Avian Evolutionary Tradition: Review of How Birds Evolve, by D. J. Futuyma, Princeton & Oxford: Princeton University Press

“…West-Eberhard (1983, 2014 defined social selection as any selection arising from direct competition between conspecifics for any resources, including, but not limited to, sexual mates. This distinction is crucial to understanding the evolution of ornamentation in age and sex classes other than adult males (e.g., Lipshutz 2017;Enbody et al 2018;Beco et al 2021;Macedo et al 2021). So, it was refreshing to see Futuyma clearly and explicitly lay out that distinction, including the fascinating case of the bright orange head plumes of American Coot nestlings, which likely evolved via competition between siblings for parental attention (Lyon et al 1994).…”

“…2021; Macedo et al. 2021). So, it was refreshing to see Futuyma clearly and explicitly lay out that distinction, including the fascinating case of the bright orange head plumes of American Coot nestlings, which likely evolved via competition between siblings for parental attention (Lyon et al.…”

The evolution of sex similarities in social signals: Climatic seasonality is associated with lower sexual dimorphism and greater elaboration of female and male signals in antbirds (Thamnophilidae)

“…However, competition for sexual and nonsexual resources and traits that mediate this competition occur in both sexes across many taxa. Notably, in species in which both sexes socially compete, sexual dimorphism of social signals tends to be lower (West-Eberhard 1983;Amundsen 2000;Rosvall 2011;Clutton-Brock and Huchard 2013;Cain and Langmore 2016;Hare and Simmons 2019;Enbody et al 2018;Odom et al 2021;Macedo et al 2021). Therefore, when females and males are subject to similar social selection pressures, strengthened competition in harsher environments could lead to the elaboration of social signals in both sexes, thereby decreasing sexual dimorphism.…”

“…Most antbird species are sexually dimorphic in plumage and songs to varying degrees (Hellmayr 1929;Zimmer and Isler 2003;Marcondes and Brumfield 2019;Beco et al 2021). In many species, both sexes engage in territory defense and parental case Oniki 1972, 1978;Seddon and Tobias 2006;Tobias et al 2011;Macedo et al 2021). In contrast, in other species, males show stronger territorial responses than females (Fedy and Stuchbury 2005;Macedo et al 2021) and females invest more in parental care than males (Oniki and Willis 1999;Reinert 2008, Bradley 2008Rompré and Robinson 2008).…”

“…In many species, both sexes engage in territory defense and parental case Oniki 1972, 1978;Seddon and Tobias 2006;Tobias et al 2011;Macedo et al 2021). In contrast, in other species, males show stronger territorial responses than females (Fedy and Stuchbury 2005;Macedo et al 2021) and females invest more in parental care than males (Oniki and Willis 1999;Reinert 2008, Bradley 2008Rompré and Robinson 2008). Therefore, antbird species may vary in social competition pressures acting on females and males.…”