Effects of acanthocephalan parasites on colour and carotenoid quantities of their intermediate host Gammarus lacustris in the context of variable lake productivity
Bibliographic record
Abstract
I studied the effects of Polymorphus paradoxus Connell and Corner and Polymorphus marilis Van Cleave on colour and carotenoid quantities of their host amphipod Gammarus lacustris G.O. Sars in seven lakes in Alberta, Canada, that differed in productivity. Polymorphus marilis induced ‘pigmentation dystrophy’ and a higher degree of blueness in both amphipod sexes than did P. paradoxus. Colour shifted toward lighter, bluer and greener tones, denoting less carotenoids, in amphipods parasitized by P. marilis. This is the first study to measure host-colour changes induced by parasites using consistent, repeatable digital analysis. Maximum carotenoid quantities were reached in hypereutrophic lakes where parasite-induced colour changes were also generally minimal. I developed regression models that accurately predict carotenoid quantities in amphipods by their colour, parasite status and water chemistry. This is the first study showing that carotenoid quantities and parasite-induced colour change in crustaceans depend on lake productivity.
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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 | 0.001 |
| 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".