Muscle Metabolic Capacities and Plasma Cortisol Levels of the Male Three‐Spine Stickleback <i>Gasterosteus aculeatus</i>: Are There “Femme Fatale” or “Macho Male” Effects?
Bibliographic record
Abstract
To evaluate whether decreases in muscle metabolic capacities and increases in plasma cortisol explain the effects of neighboring conspecifics on male three-spine sticklebacks Gasterosteus aculeatus, we housed mature males alone, with a mature female, or with a rival mature male. The neighbors were separated from the focal male by a partition that allowed him to smell, see, and hear his neighbor. In the first experiment, focal males were allowed to reproduce, whereas in the second experiment, no reproduction occurred. Coloration and behaviors were monitored while the males tended their nests (or for the same period in the second experiment). The presence of a neighbor markedly affected the reproductive coloration of the focal male, with solitary males being less colorful than males housed with a rival male or a female. Solitary males showed greater aggression toward a model male stickleback than did males with neighbors. The presence of neighbors affected the anatomic and metabolic characteristics of the focal males primarily during nesting, when males housed with rival males had a lower hepatosomatic index and lower activities of mitochondrial and glycolytic enzymes in the axial muscle than did solitary males or males housed with females. Cortisol levels were highly variable in nesting males and did not differ with social condition but were higher in males that had been quick to construct their nests. On the other hand, when focal males were not provided with nesting material, solitary males tended to have lower cortisol levels than did males housed with rival males. While these results do not provide a mechanism for a "femme fatale" effect, they indicate that nesting males decrease metabolic status when housed with rival "macho males."
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".