Risk allocation in a freshwater gastropod

To balance the basic needs of organisms, internal and external cues are used to inform the optimal behavioral strategy. Some of the best-studied related cognitive rules have emerged in predator-prey contexts, such as the threat-sensitivity hypothesis, which postulates that prey should adjust their antipredator behavior in accordance with the level of risk. Extending this theory, the risk allocation hypothesis posits that under long-term sustained high predation risk, individuals should decrease their antipredator responses towards risky stimuli so as to meet their energetic demands. Evidence for the risk allocation hypothesis has been mixed in invertebrates, particularly in gastropods that are classic model systems for antipredator responses. This may be due to past studies frequently lacking sham controls and/or sufficient certainty about the risk regime. The present study in the aquatic gastropod Physella acuta controls for these factors by crossing long-term background risk, i.e., li..., , # Risk allocation in a freshwater gastropod

Dataset DOI: [10.5061/dryad.tqjq2bwbb](10.5061/dryad.tqjq2bwbb)

## Description of the data and file structure

This data originates from a laboratory study on the freshwater gastropod *Physella acuta*. In a split-clutch design, individuals were raised under either low or high background risk (high-risk: conspecific alarm cues or low-risk: a water control). At 28 days age, their crawl-out behavior was observed prior and after the addition of either a low-risk or high-risk cue; stimulus risk was fully crossed with background risk. Afterwards, we also assessed morphology in a subset of experimental snails. Detailed information on how the data was obtained is contained in the corresponding manuscript.

### Files and variables

**Description of data files**

**2025-05-21-crawl-datasheet-full-wide.csv** – File containing per-tank behavioral and morphological data in wide format for analysis.

**2025-05-21-crawl-datasheet-long-interval.csv** – File...,