Short photoperiods end autumn migration in a naïve diurnal migrant
Bibliographic record
Abstract
Many migratory animals use daylength, or photoperiod, to signal when to migrate and transition between annual phenological states. Whether animals use photoperiod as a temporal or spatial cue while migrating, however, requires additional empirical support. We used hatch-year dunnocks, Prunella modularis (a songbird), caught during their first migration in southern Sweden to elucidate whether migratory animals incorporate photoperiod as a spatiotemporal cue into their endogenous migratory program during migration. We exposed the migratory-naïve to light environments that simulated either the local photic conditions or a shorter daylength and larger transitions between photoperiods. All birds experienced local geomagnetic conditions. We hypothesized that migratory dunnocks used photoperiod to inform their first migration and predicted that the experimental treatment represented either a spatial displacement to the north or a temporal advancement towards winter at the capture site compared to the local control conditions. We found, though, that the short photoperiods terminated the expression of the migratory phenotype compared to controls by reducing body mass gain and ending migratory activity, indicating that the endogenous migratory program integrates photoperiod during migration. The incorporation of photoperiod into the endogenous program may complement geomagnetic cues to ensure ending migration at the correct time and location. The incorporation of photoperiod can also provide a mechanism that facilitates poleward shifts of overwintering distribution under climate change by allowing migrants to overwinter in newly suitable habitat at higher latitude (i.e. short stopping).
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 | 0.000 | 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) | 0.003 | 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".