Maternal glucocorticoid levels during incubation predict breeding success, but not reproductive investment, in a free-ranging bird
| Autor: | Robby R. Marrotte, Devin Fischer, Eunice H. Chin, Smolly Coulson, Gary Burness |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
0106 biological sciences
Avian endocrine system QH301-705.5 Science Zoology Context (language use) Breeding Biology 010603 evolutionary biology 01 natural sciences General Biochemistry Genetics and Molecular Biology Birds 03 medical and health sciences chemistry.chemical_compound Stressor Stress Physiological Corticosterone Fitness Tree swallow polycyclic compounds medicine Animals Biology (General) Glucocorticoids Incubation 030304 developmental biology Egg incubation 0303 health sciences Reproductive success Hatching Reproduction Fledge biology.organism_classification Adaptation Physiological chemistry Tachycineta bicolor Female General Agricultural and Biological Sciences Biomarkers hormones hormone substitutes and hormone antagonists Glucocorticoid Research Article medicine.drug |
| Zdroj: | Biology Open article-version (VoR) Version of Record Biology Open, Vol 9, Iss 10 (2020) |
| ISSN: | 2046-6390 |
| DOI: | 10.1242/bio.045898 |
| Popis: | The hormone corticosterone (CORT) has been hypothesized to be linked with fitness, but the directionality of the relationship is unclear. The ‘CORT-fitness hypothesis’ proposes that high levels of CORT arise from challenging environmental conditions, resulting in lower reproductive success (a negative relationship). In contrast, the CORT-adaptation hypothesis suggests that, during energetically demanding periods, CORT will mediate physiological or behavioral changes that result in increased reproductive investment and success (a positive relationship). During two breeding seasons, we experimentally manipulated circulating CORT levels in female tree swallows (Tachycineta bicolor) prior to egg laying, and measured subsequent reproductive effort, breeding success, and maternal survival. When females were recaptured during egg incubation and again during the nestling stage, the CORT levels were similar among individuals in each treatment group, and maternal treatment had no effect on indices of fitness. By considering variation among females, we found support for the CORT-adaptation hypothesis; there was a significant positive relationship between CORT levels during incubation and hatching and fledging success. During the nestling stage CORT levels were unrelated to any measure of investment or success. Within the environmental context of our study, relationships between maternal glucocorticoid levels and indices of fitness vary across reproductive stages. Summary: Levels of the stress biomarker corticosterone predict breeding success in female tree swallows. However, correlations between hormone levels and fitness differ between life-history stages. |
| Databáze: | OpenAIRE |
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