TY - JOUR
T1 - Species divergence in sexually selected traits
T2 - Increase in song elaboration is related to decrease in plumage ornamentation in finches
AU - Badyaev, Alexander V.
AU - Hill, Geoffrey E.
AU - Weckworth, Byron V.
PY - 2002
Y1 - 2002
N2 - Elaborate plumage and complex songs of male birds are two of the best-known examples of sexually selected traits, yet the interaction between these traits is poorly understood. Theory suggests that among a suite of potential displays, animals will emphasize traits that are most conspicuous, least costly, or best signal condition and reduce display of other traits. Here we examined the relationship between song and plumage elaborations in cardueline finches, songbirds that are highly variable in plumage displays and songs, but that share a similar mating system. We statistically controlled for body mass, habitat characteristics, and phylogenetic relationships and found that across species song complexity was strongly negatively related to elaboration of plumage ornamentation. When plumage coloration was partitioned into carotenoid-based and melanin-based components, song complexity was negatively related to elaboration of male carotenoid-based coloration but unrelated to elaboration of melanin-based coloration. These observations support the idea that, for condition-dependent traits, animal species trade off trait expression in response to changes in the costs or the information content of these traits. We discuss several alternative explanations for the observed pattern.
AB - Elaborate plumage and complex songs of male birds are two of the best-known examples of sexually selected traits, yet the interaction between these traits is poorly understood. Theory suggests that among a suite of potential displays, animals will emphasize traits that are most conspicuous, least costly, or best signal condition and reduce display of other traits. Here we examined the relationship between song and plumage elaborations in cardueline finches, songbirds that are highly variable in plumage displays and songs, but that share a similar mating system. We statistically controlled for body mass, habitat characteristics, and phylogenetic relationships and found that across species song complexity was strongly negatively related to elaboration of plumage ornamentation. When plumage coloration was partitioned into carotenoid-based and melanin-based components, song complexity was negatively related to elaboration of male carotenoid-based coloration but unrelated to elaboration of melanin-based coloration. These observations support the idea that, for condition-dependent traits, animal species trade off trait expression in response to changes in the costs or the information content of these traits. We discuss several alternative explanations for the observed pattern.
KW - Carduelinae
KW - Multiple sexual signals
KW - Plumage ornamentation
KW - Song elaboration
UR - http://www.scopus.com/inward/record.url?scp=0036126685&partnerID=8YFLogxK
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U2 - 10.1111/j.0014-3820.2002.tb01350.x
DO - 10.1111/j.0014-3820.2002.tb01350.x
M3 - Article
C2 - 11926507
AN - SCOPUS:0036126685
SN - 0014-3820
VL - 56
SP - 412
EP - 419
JO - Evolution; international journal of organic evolution
JF - Evolution; international journal of organic evolution
IS - 2
ER -