Factors influencing the coexistence of bromeliad-dwelling chironomids on Ilha do Cardoso, Brazil
Bibliographic record
Abstract
Species interactions can influence the spatial distribution of organisms and the composition of local communities. To investigate how interactions influence the coexistence of invertebrates living in bromeliad phytotelmata, I combined methodological development and empirical exploration with the aim of understanding: 1) Which species in a community show signs of strong interactions, 2) Whether predators influence the outcome of competitive interactions and 3) Whether equalizing or stabilizing interactions between species change depending on context. To detect interactions between species given observational field data, I designed a method of finding negative co-occurrence patterns (using checkerboard units) between species based on their abundances in nature. Using this method, I found that three chironomid (Diptera: Chironomidae) species showed very strong negative co-occurrence patterns, suggesting that they experience net negative interactions (e.g. competition) or habitat filtering. Next, I performed a predator-addition experiment to assess the importance of predators in mediating the coexistence of the three chironomid species. Three predator species were added to bromeliads containing the three chironomid species. Although field observations suggested that at least one chironomid species should improve performance in the absence of predators, there was only a slight differential response to predators. Furthermore, one species of chironomid was competitively superior to the others in both the presence and absence of predators. We suspect that differing habitat preferences and the presence of other prey may be more important to coexistence than the presence or absence of predators alone. Finally, I performed an experiment to assess how habitat and ontogeny affect the outcome of competition between the two most common chironomid species. When reared at the same body size, the two chironomids exhibited a stable relationship that we term here asymmetric equivalence: in one species experiences the world neutrally but the other does not. However, when species differed in their ontogenetic stage, the asymmetric equivalence disappeared. Taking all three studies together, I found that competition, but not predation, is an important factor in chironomid coexistence, but that differences in context lead to different coexistence outcomes.
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 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.001 |
| 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".