Disentangling the direct, indirect, and combined effects of experimental warming on a plant–insect herbivore interaction
Bibliographic record
Abstract
Abstract There is increasing evidence that climate warming will have both direct and indirect effects on species. Whereas the direct effects of climate warming represent the proximate physiological consequences of changing abiotic conditions, the indirect effects of climate change reflect changes mediated by at least one other interacting species. The relative importance of these two kinds of effects has been unclear, limiting our ability to generalize the response of different species to climate change. Here, we used a series of experiments to disentangle some of the key direct and indirect effects of warming on the growth of monarch butterfly caterpillars (Danaus plexippus) and showy milkweed plants (Asclepias speciosa) during a window of rapid growth for both species. The effects of warming differed between direct, indirect, and combined effect experiments. Warming from 26°C to 30°C directly increased the growth of both monarch larvae and milkweeds, with monarch and milkweed growth rates showing similar sensitivity to warming. However, in a subsequent experiment, we did not observe significantly increased growth when comparing caterpillars and plants reared at 27°C and 31°C, suggesting that small differences can change the direct effects of warming. When caterpillars that were maintained at laboratory temperatures were fed leaves from host plants that were exposed to warmer temperatures, warming had a negative indirect effect on larval growth rates likely mediated by decreases in milkweed leaf quality. In experiments combining direct and indirect effects, we observed a net positive effect of warming on larval growth rates. Warming had no combined effects on milkweed growth, potentially due to opposing positive direct and negative indirect effects on growth mediated via increased monarch herbivory. These results show how variability among the direct, indirect, and combined effects of even relatively simple, short‐term climatic perturbations can present challenges for predicting the broader effects of climatic warming in multispecies communities.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.004 | 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".