DOI: 10.5061/dryad.r7sqv9sqv
title: Ontogenetic modulation of risk perception and decision making in larval anurans

description: To select cost-effective defensive responses, prey need to fine-tune
 defensive responses by integrating reliable information about predation
 risk with their own physiological state and energetic needs. While it is
 difficult to assess the actual perceived level of risk, we hypothesized
 that stage-related variation in defensive responses to different predation
 cue concentrations may offer valuable insight into decision making under
 predation risk. To test this hypothesis, we examined Italian agile frog
 (Rana latastei) tadpoles’ sensitivity to both fed and fasted predator cues
 at varying concentrations (1:1, 1:10, 1:100, 1:500) and two developmental
 stages (26-28 and 30-31 Gosner stages). Younger tadpoles responded
 similarly to both types of cues, by markedly lowering activity levels when
 exposed at 1:1 and 1:10 cues, while no significant difference from the
 control was recorded at low cue concentrations. Older tadpoles in
 contrast, showed heightened sensitivity to fed predator cues, responding
 even at 1:100, while largely ignoring cues from fasted predators. These
 results highlight a developmental shift in risk assessment, consistent
 with changing trade-offs between predator avoidance and other life-history
 priorities. This shift suggests that ontogenetic changes shape not only
 the strength but also the selectivity of perceived risk, reflecting more
 nuanced decision-making as developmental priorities evolve.
description: # Ontogenetic Modulation of Risk Perception and Decision Making in Larval
 Anurans ## Overview This dataset contains behavioural measurements of
 larval amphibians (Rana latastei) used to investigate how developmental
 stage modulates antipredator responses to predator chemical cues. The
 experiment tested the combined effects of predator diet, cue
 concentration, and ontogeny on activity and movement. The data support the
 findings reported in the manuscript Ontogenetic Modulation of Risk
 Perception and Decision Making in Larval Anurans. ## Files and Variables
 ### **Data file** * `data.txt`: Tab-delimited text file containing all
 behavioral data. ### **Variables** * `id`: Unique identifier for each
 individual tadpole. * `date`: Date of the video recording. * `session`:
 Developmental stage (1 = one week post-hatching; 2 = three weeks
 post-hatching). * `cod_video`: Identifier of the video file. * `tub`:
 Identifier of the tub within the experimental arena. * `clutch`:
 Identifier of the clutch from which the tadpole originated. * `stimulus`:
 Predator chemical cue type and concentration (fed or unfed at 1:1, 1:10,
 1:100, or 1:500 dilution). * `tot.time_frozen_s`: Total time (in seconds)
 the tadpole remained inactive during the pre-stimulus period. *
 `tot.time_frozen_s_post`: Total time inactive (in seconds) during the
 post-stimulus period. * `total_distance`: Distance covered (in
 millimetres) during the pre-stimulus period. * `total_distance_post`:
 Distance covered (in millimetres) during the post-stimulus period. ## Data
 collection -Experiments were conducted in indoor laboratory conditions in
 northern Italy between March and April 2023. Each individual was filmed
 once during a -36-minute trial comprising pre- and post-stimulus phases.
 ## Code and Analysis ### Script * `Script.R`: R script used for all
 statistical analyses, including data import, preprocessing, model fitting
 (GLMM and Bayesian models), and visualization of results. ### Software
 Analyses were conducted in **R (version 4.3.2)** using the following
 packages: * `glmmTMB`, `brms`, `DHARMa`, `emmeans`, `ggplot2`, and others
 (see script header for details). ## Notes * This dataset and code are
 provided to ensure full reproducibility of all analyses and figures
 reported in the manuscript.