A simple explanation for the evolution and maintenance of temperature-dependent sex determination
Bibliographic record
Abstract
The Charnov-Bull model stipulates that environmental sex determination (ESD) is favoured when fitness of the sexes responds differently to the environment. However, Charnov-Bull has not yet been broadly successful in explaining the adaptive significance of temperature-dependent sex determination (TSD), a form of ESD. Specifically, there is no broad and convincing explanation for the occurrence of a sex-by-incubation temperature interaction for fitness. Here, I point out that the Trivers-Willard model, which predates Charnov-Bull, has never been applied broadly to explain the adaptive significance of TSD. Under Trivers-Willard, a sex-by-environment interaction for fitness occurs along the axis of individual condition (general health, vigour, etc), as male fitness is relatively sensitive to condition by virtue of relatively strong sexual selection; this occurs regardless of the direction of sexual-size dimorphism. I propose that incubation temperature affects condition, and TSD evolves so that males arise from relatively high-quality incubation environments; I call this the Mighty Males hypothesis. Re-examination of existing literature provides significant support to Mighty Males and its assumptions. Mighty Males can also explain why aspects of the environment other than temperature affect sex in some TSD species. Ultimately, I provide a simple explanation for TSD, and I suggest directions for future work.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.002 | 0.009 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.004 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.030 | 0.022 |
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".