Abstract
Secondary sexual traits and associated behaviors can be influenced by environmental factors such as exposure to stressors. Such effects may be mediated by the physiological stress response, which is typified by the release of glucocorticoid hormones. The effects of glucocorticoids on sexual traits such as plumage and display coloration have most commonly been studied in isolation rather than in conjunction with other pertinent aspects of signalling, such as behavior and habitat use, though these have substantial potential to alter signal perception. Here we test the effects of corticosterone (CORT), a common glucocorticoid, on a secondary sexual trait (badge coloration) in male eastern fence lizards (Sceloporus undulatus), and behaviors associated with its expression. We show that neither baseline nor experimentally manipulated CORT levels were associated with badge coloration. Further, elevation of CORT levels in the field did not alter signalling or associated territorial behaviors. There was a trend for CORT-treatment to influence perch height selection, which may influence signal perception. We suggest that future studies investigating the effects of environmental stressors and associated physiological changes on secondary sexual traits should consider behaviors and ecology relevant to signal perception in order to best understand the influence of stressors in nature.
Highlights
Secondary sexual traits - such as bright plumage or elaborate ornamentation, and associated signalling behaviors - are important for territoriality and mate choice[1,2,3]
Effects of stressor exposure on sexual traits are likely to be mediated by the physiological stress response, a suite of neuroendocrine processes characterized by activation of the hypothalamic-pituitary-adrenal axis (HPA) and subsequent release of glucocorticoid hormones which facilitate appropriate reactions to and recovery from stressors[17,18,19]
CORT level had a significant effect on within-individual variation in Red color values; higher CORT levels were associated with higher Red values in chest badge segments, but reduced Red values in chin segments (F3,41 = 3.57, P = 0.02)
Summary
Secondary sexual traits - such as bright plumage or elaborate ornamentation, and associated signalling behaviors - are important for territoriality and mate choice[1,2,3]. We test the effects of physiological stress on male secondary sexual traits and behaviors relevant to their expression, in the eastern fence lizard, Sceloporus undulatus. The ventral badges of Sceloporus lizards are cryptic unless displayed[35,36,39], including through conspicuous “headbob” and “pushup” displays that expose the gular and abdominal regions[40,41,42] Previous work in this genus has linked plasma CORT levels with habitat use, with hatchlings moving to higher elevations when CORT levels were experimentally elevated[43]. Any changes in secondary coloration and its behavioral expression due to exposure to a stressor are likely to have fitness-relevant outcomes
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
