Larval development and diapause induction under climate change: an experimental test with the Wall Brown butterfly

Under climate change, organisms with complex life cycles like insects are confronted with environmental cues that may interfere with their life cycle regulation, including diapause induction. Maladaptive responses to novel conditions may contribute to local or regional population declines and extinctions. In NW-Europe, the Wall Brown butterfly (Lasiommata megera) is a multivoltine species whose regional decline has been hypothesised to be related to recent warming in late summer and autumn increasing the probability of producing a late third generation instead of going into larval diapause to hibernate. To test this lost generation hypothesis, we exposed young larvae of different population origins to outdoor conditions and in situ warming (i.e., increased temperature at the level of the host plant by 0.5 to 3°C depending on the month). The warming treatment resulted in shorter larval developmental times and reduced adult body size. However, the population origin and the temperature tre..., , # Kaiser & Van Dyck, 2025. Larval development and diapause induction under climate change: an experimental test with the wall brown butterfly

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This dataset accompanies the study “Larval development and diapause induction under climate change: an experimental test with the wall brown butterfly”.
The dataset is provided as a single Excel file containing two worksheets: “Development and survival” and “Body size and dev. time”.
All data are raw (unprocessed) and correspond to individual-level measurements collected during the experiment.

The “Development and survival” sheet contains data on larval development pathways (direct development vs. diapause) and larval survival outcomes.

The “Body size and dev. time” sheet contains data on developmental time and adult body size (estimated from wing area).
Developmental time and wing area are reported only for individuals that emerged by the end of the first autumn (i.e., adults that followed a direct development pathway).

## Descriptions

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