TY - JOUR
T1 - Multiple signaling in a variable environment
T2 - expression of song and color traits as a function of ambient sound and light
AU - Simpson, Richard K.
AU - McGraw, Kevin
N1 - Funding Information:
We would like to thank I. Chiver for providing natural history and tracking knowledge on the Red-throated Ant-tanagers; W. Halfwreck for providing the SongMeter and aid in ambient noise analysis; B.M. Seymoure for providing the camera setup and aid in canopy cover analysis; S. Pratt for help with statistical analyses, and J.M. Touchton for instrumental help with supplies and the development of this project. We thank M.E. Duell, M.B. Simpson and D.A. Simpson for their incredible support and for help in the field, and M.E. Duell, R.A. Ligon, B.M. Seymoure, L. Weber-Grullon, the McGraw lab, and three anonymous reviewers for helpful comments on this manuscript. We would like to thank the Society for the Study of Evolution Rosemary Grant Research Award and the Arizona State University chapter of Sigma Xi for funding this study. Finally, we would like to thank both Arizona State University and the Smithsonian Tropical Research Institute for use of their facilities and proving additional support and funding to the project.
Funding Information:
We would like to thank I. Chiver for providing natural history and tracking knowledge on the Red-throated Ant-tanagers; W. Half-wreck for providing the SongMeter and aid in ambient noise analysis; B.M. Seymoure for providing the camera setup and aid in canopy cover analysis; S. Pratt for help with statistical analyses, and J.M. Touchton for instrumental help with supplies and the development of this project. We thank M.E. Duell, M.B. Simpson and D.A. Simpson for their incredible support and for help in the field, and M.E. Duell, R.A. Ligon, B.M. Seymoure, L. Weber-Grullon, the McGraw lab, and three anonymous reviewers for helpful comments on this manuscript. We would like to thank the Society for the Study of Evolution Rosemary Grant Research Award and the Arizona State University chapter of Sigma Xi for funding this study. Finally, we would like to thank both Arizona State University and the Smithsonian Tropical Research Institute for use of their facilities and proving additional support and funding to the project.
Publisher Copyright:
© 2018 The Association for Tropical Biology and Conservation
PY - 2018/5
Y1 - 2018/5
N2 - Many animals communicate using more than one signal, and several hypotheses exist to explain the evolution of multiple signals. However, these hypotheses typically assume static selection pressures, and previous work has not addressed how spatial and temporal environmental variation can shape variation in signaling systems. In particular, environmental variability, such as ambient lighting or noise, may affect efficacy (e.g., detectability/perception by receivers) of signals. To examine how signal expression varies intraspecifically as a function of habitat characteristics, we evaluated relationships between spatial environmental variation and song and plumage color expression in a tropical songbird, the Red-throated Ant-tanager (Habia fuscicauda) in Panama. We recorded male ant-tanager song, plucked feathers to measure coloration, and quantified the acoustic and light environments from each male's territory. In addition, we took several morphological measurements from each male to assess the potential information content of song and plumage color. We found that males with redder and more saturated crown plumage occurred on darker territories, and males that sang shorter and lower frequency songs occurred on noisier territories. We also found that more colorful males tended to sing longer and lower frequency songs. Finally, we found that song and color correlated similarly with male morphology (e.g., tarsus length, body mass). Altogether, these results indicate that spatial variation in the environment is related to male coloration and song, and that males might be optimizing color and song expression for their particular territorial environment.
AB - Many animals communicate using more than one signal, and several hypotheses exist to explain the evolution of multiple signals. However, these hypotheses typically assume static selection pressures, and previous work has not addressed how spatial and temporal environmental variation can shape variation in signaling systems. In particular, environmental variability, such as ambient lighting or noise, may affect efficacy (e.g., detectability/perception by receivers) of signals. To examine how signal expression varies intraspecifically as a function of habitat characteristics, we evaluated relationships between spatial environmental variation and song and plumage color expression in a tropical songbird, the Red-throated Ant-tanager (Habia fuscicauda) in Panama. We recorded male ant-tanager song, plucked feathers to measure coloration, and quantified the acoustic and light environments from each male's territory. In addition, we took several morphological measurements from each male to assess the potential information content of song and plumage color. We found that males with redder and more saturated crown plumage occurred on darker territories, and males that sang shorter and lower frequency songs occurred on noisier territories. We also found that more colorful males tended to sing longer and lower frequency songs. Finally, we found that song and color correlated similarly with male morphology (e.g., tarsus length, body mass). Altogether, these results indicate that spatial variation in the environment is related to male coloration and song, and that males might be optimizing color and song expression for their particular territorial environment.
KW - Habia fuscicauda
KW - birdsong
KW - coloration
KW - environmental variation
KW - multi-modal signals
KW - signal efficacy
UR - http://www.scopus.com/inward/record.url?scp=85048033872&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85048033872&partnerID=8YFLogxK
U2 - 10.1111/btp.12528
DO - 10.1111/btp.12528
M3 - Article
AN - SCOPUS:85048033872
SN - 0006-3606
VL - 50
SP - 531
EP - 540
JO - Biotropica
JF - Biotropica
IS - 3
ER -