TY - JOUR
T1 - Testosterone, endurance, and Darwinian fitness
T2 - Natural and sexual selection on the physiological bases of alternative male behaviors in side-blotched lizards
AU - Sinervo, Barry
AU - Miles, Donald B.
AU - Frankino, W. Anthony
AU - Klukowski, Matthew
AU - DeNardo, Dale F.
N1 - Funding Information:
We thank P. Stadler and R. Schrimp for allowing us to work on their land and E. Ketterson for her lab space. B. Sinervo was supported by NSF Grants DEB 93-07999 and IBN 96-31757, D. B. Miles was supported by an OURC Ohio Board of Regents Research Challenge Grant and NSF Grant IBN 92-07895, W. A. Frankino and M. Klukowski were both supported by the Center for the Integrative Study of Animal Behavior, and D. F. DeNardo was supported by an NIH postdoctoral fellowship.
PY - 2000
Y1 - 2000
N2 - The mechanistic bases of natural and sexual selection on physiological and behavioral traits were examined in male morphs of three colors of the side-blotched lizard, Uta stansburiana. Orange-throated males are aggressive and defend large territories with many females. Blue-throated males defend smaller territories with fewer females; however, blue-throated males assiduously mate guard females on their territory. Yellow-throated males do not defend a territory, but patrol a large home range. They obtain secretive copulations from females on the territories of dominant males. Males with bright orange throats had higher levels of plasma testosterone (T), endurance, activity, and home range size and concomitantly gained greater control over female home ranges than blue-or yellow-throated males. Experimentally elevating plasma T in yellow-and blue-throated males increased their endurance, activity, home range size, and control over female territories to levels that were seen in unmanipulated orange-throated males that had naturally high plasma T. However, the enhanced performance of orange-throated males is not without costs. Orange-throated males had low survival compared to the other morphs. Finally, some yellowthroated males transformed to a partial blue morphology late in the season and the endurance of these transforming yellow-throated males increased from early to late in the season. In addition, yellow-throated males that transformed to blue also had significantly higher plasma T late in the season compared to the plasma T earlier in the season. T appears to play an important role in the physiological changes that all three color morphs undergo during the process of maturation. In some yellow males, T plays an additional role in plastic changes in behavior and physiology late in the reproductive season. We discuss natural and sexual selection on physiological and behavioral traits that leads to the evolution of steroid regulation in the context of alternative male strategies. (C) 2000 Academic Press.
AB - The mechanistic bases of natural and sexual selection on physiological and behavioral traits were examined in male morphs of three colors of the side-blotched lizard, Uta stansburiana. Orange-throated males are aggressive and defend large territories with many females. Blue-throated males defend smaller territories with fewer females; however, blue-throated males assiduously mate guard females on their territory. Yellow-throated males do not defend a territory, but patrol a large home range. They obtain secretive copulations from females on the territories of dominant males. Males with bright orange throats had higher levels of plasma testosterone (T), endurance, activity, and home range size and concomitantly gained greater control over female home ranges than blue-or yellow-throated males. Experimentally elevating plasma T in yellow-and blue-throated males increased their endurance, activity, home range size, and control over female territories to levels that were seen in unmanipulated orange-throated males that had naturally high plasma T. However, the enhanced performance of orange-throated males is not without costs. Orange-throated males had low survival compared to the other morphs. Finally, some yellowthroated males transformed to a partial blue morphology late in the season and the endurance of these transforming yellow-throated males increased from early to late in the season. In addition, yellow-throated males that transformed to blue also had significantly higher plasma T late in the season compared to the plasma T earlier in the season. T appears to play an important role in the physiological changes that all three color morphs undergo during the process of maturation. In some yellow males, T plays an additional role in plastic changes in behavior and physiology late in the reproductive season. We discuss natural and sexual selection on physiological and behavioral traits that leads to the evolution of steroid regulation in the context of alternative male strategies. (C) 2000 Academic Press.
KW - Alternative male strategies
KW - ESS
KW - Endurance
KW - Territorial behavior
KW - Testosterone
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U2 - 10.1006/hbeh.2000.1622
DO - 10.1006/hbeh.2000.1622
M3 - Article
C2 - 11104640
AN - SCOPUS:0033635620
SN - 0018-506X
VL - 38
SP - 222
EP - 233
JO - Hormones and Behavior
JF - Hormones and Behavior
IS - 4
ER -