In the four-eyed fish ( <i>Anableps anableps</i> ), the regions of the retina exposed to aquatic and aerial light do not express the same set of opsin genes
Bibliographic record
Abstract
The four-eyed fish, Anableps anableps, has eyes with unusual morphological adaptations for simultaneous vision above and below water. The retina, for example, is divided such that one region receives light from the aerial field and the other from the aquatic field. To understand better the adaptive value of this partitioned retina, we characterized photoreceptor distribution using in situ hybridization. Cones expressing sws1, sws2b and rh2-2 (i.e. UV, and short wavelength-sensitive) opsins were found throughout the retina, whereas cones expressing rh2-1 (middle wavelength-sensitive) were largely limited to the ventral retina and those expressing lws (long wavelength-sensitive) opsins were only expressed in the dorsal retina. We next asked when this pattern evolved relative to the 'four-eyed' morphology. We characterized opsin expression in Jenynsia onca, a member of the sister genus to Anableps with typical teleost eye morphology. In J. onca, sws1, sws2b, rh2-2 and rh2-1 opsins were expressed throughout the retina; while lws opsins were not expressed in the ventral retina. Thus, the change that coincides with the evolution of unusual anablepid eye morphology is the loss of rh2-1 expression in the dorsal retina, probably to accommodate increased lws opsin expression. The retinal area that samples aerial light appears not to have changed with respect to photoreceptor transcription.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 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 | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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 teacher head, 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".