Understanding Color Polymorphism in the Sea Star, Pisaster ochraceus, Through Activity Levels and Dietary Preference
Bibliographic record
Abstract
Color polymorphism is found in a wide array of organisms ranging from copepods to black bears. Pisaster ochraceus, an intertidal sea star on the North Pacific West Coast, shows a striking color polymorphism including a range of orange, brown, maroon, and purple. Pisaster shows extensive geographic color variation, with >95% frequency of bright purple Pisaster in the Vancouver region; while the open pacific coast has a frequency distribution of 6-28% orange, 68-90% reddish-brown to dull purple, and a small percentage of bright purple. Maintenance of color polymorphism remains unknown, but one hypothesis suggests an underlying genetic component with regional-scale variation controlled by an ecological factor. Two ecological factors suggested are diet and salinity. This study analyzes the differences in dietary preference and activity levels between the color morphs in Bamfield, British Columbia. Pisaster was binned into two colors, orange and purple, for statistical analysis. Feeding laboratory trials showed no preference between the color morphs for Mytilus edilus or Mytilus californianus. Self-righting trials were performed in a low (20 psu) and controlled (35 psu) salinity and no significant difference was found between the color morphs. Interestingly, the activity levels of orange color morphs were not significantly different between low and control salinity. The results suggest there are ecological differences between the color morphs that still need to be evaluated.
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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 | 0.000 |
| 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".