Evolutionary drivers of seasonal plumage colours: colour change by moult correlates with sexual selection, predation risk and seasonality across passerines

Abstract

Some birds undergo seasonal colour change by moulting twice each year, typically alternating between a cryptic, non‐breeding plumage and a conspicuous, breeding plumage (‘seasonal plumage colours’). We test for potential drivers of the evolution of seasonal plumage colours in all passerines (N = 5901 species, c. 60% of all birds). Seasonal plumage colours are uncommon, having appeared on multiple occasions but more frequently lost during evolution. The trait is more common in small, ground‐foraging species with polygynous mating systems, no paternal care and strong sexual dichromatism, suggesting it evolved under strong sexual selection and high predation risk. Seasonal plumage colours are also more common in species predicted to have seasonal breeding schedules, such as migratory birds and those living in seasonal climates. We propose that seasonal plumage colours have evolved to resolve a trade‐off between the effects of natural and sexual selection on colouration, especially in seasonal environments.

Female prereproductive coloration reduces mating harassment in damselflies

“…Prereproductive females can avoid mating harassment by staying away from the breeding area (Hinnekint 1987;Corbet 1999), displaying refusal behavior (Chan et al 2009), signaling unwillingness via pheromones (Ferrero et al 2013), mimicking male coloration (Hammers et al 2009;Huang and Reinhard 2012;Willink et al 2019), or avoiding male detection by inconspicuous coloration (Baldauf et al 2011;Fincke 2015;Vilela et al 2017). Dull coloration further reduces predator and prey detection, which in turn increases survival and foraging (Outomuro et al 2017;McQueen et al 2019). Dull coloration of sexually immature females therefore has evolved via natural and sexual selection and is predominant in nature (Corbet 1999;McQueen et al 2019).…”

“…Dull coloration further reduces predator and prey detection, which in turn increases survival and foraging (Outomuro et al 2017;McQueen et al 2019). Dull coloration of sexually immature females therefore has evolved via natural and sexual selection and is predominant in nature (Corbet 1999;McQueen et al 2019). Yet surprisingly, conspicuous female coloration occurs in some prereproductive females, especially in damselflies (Corbet 1999;Hammers et al 2009), with this phenomenon remains an evolutionary enigma.…”

Revealing the colourful side of birds: spatial distribution of conspicuous plumage colours on the body of Australian birds

“…One straightforward overarching prediction that can already be made is that differences in conspicuousness between exposed and hidden body parts should be more marked for species exposed to higher predation risk, such as smaller species that inhabit open habitats (McQueen et al 2019). Future work should therefore move beyond the identification of general patterns (as was the intention here) and try to make sense of variation between species or clades.…”

“…These should spell out why different ecological conditions should lead to the evolution of different kinds of spatial arrangements of conspicuously coloured body parts. One straightforward overarching prediction that can already be made is that differences in conspicuousness between exposed and hidden body parts should be more marked for species exposed to higher predation risk, such as smaller species that inhabit open habitats (McQueen et al 2019). However, whether and how conspicuousness translates into higher predation risk across species can vary substantially (Götmark 1994, Götmark and Hohlfält 1995, Götmark 1997, Huhta et al 2003, Post and Götmark 2006, McQueen et al 2017, Cain et al 2019) and this may further obscure any general patterns.…”

Partial or complete? The evolution of post‐juvenile moult strategies in passerine birds

“…(a) Body mass (log 10 -transformed, N = 1,287 species) was obtained mainly from Dunning et al (Dunning, 2008) and Wilman et al (2014) as collated by Mcqueen et al (2019). (b) Migration distance (in km, data for N = 1,315 species) was obtained from Dufour et al (2020) (variable called 'distance_quanti_ALL' in their dataset).…”