Data from: Shifting balances in the weighting of sensory modalities are predicted by divergence in brain morphology in incipient species of Heliconius butterflies
Data files
Mar 07, 2022 version files 24.20 KB
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README.md
1.55 KB
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Sensory_fulldata_DDD.xlsx
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Feb 27, 2025 version files 24.88 KB
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README.md
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Sensory_fulldata2_DDD.xlsx
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Abstract
Integrating and weighting sensory perception across modalities is crucial to how animals adapt to their environment. Divergence in brain structure is often in sensory processing regions, suggesting that investment reflects ecological needs. Here, we use two parapatric closely related species, Heliconius erato cyrbia and Heliconius himera, to test the hypothesis that divergence in sensory brain regions affects foraging decisions. These butterflies are isolated across an ecological gradient, which is linked to differences in brain morphology, with H. e. cyrbia investing more in visual centres and H. himera investing in olfactory centres. Here, we demonstrate that these two species vary in how they associate visual and olfactory cues with positive food rewards. We found that when individuals were trained on paired olfactory and visual stimuli, then presented with these stimuli in conflict, they showed distinct behavioural responses. Heliconius himera was more likely to favour positive olfactory cues than H. e. cyrbia, which favoured visual cues regardless of the paired stimulus. This suggests that these species have diverged in the emphasis placed on these different sensory domains during foraging, consistent with observed differences in brain morphology. This result strengthens evidence that speciation initiated by local adaptation is partly facilitated by changes in the neural basis of key behavioural functions.
https://doi.org/10.5061/dryad.dbrv15f0h
Description of the data and file structure
All experiments were recorded using an action camera (GoPro©) during the first 30 min in which flowers were presented. The colour assay was recorded every day, while the odour and conflict assays were recorded on the first, fourth and fifth day due to the reduction of work during the early stages of the Covid-19 pandemic. Using the video footage, the total number of feeding attempts (defined by proboscis extensions) were counted. The data are a cumulative result of all individuals divided in groups (individuals which were tested together). To calculate differences between species, we used linear mixed-effect models (‘glmer’) implemented with the ‘lme4’ package (Bates et al., 2015) using a Poisson distribution, including day and species as fixed factors and group as random factor, followed by analysis of deviance and Tukey’s post hoc tests in R (R Core Team, 2020). Student’s t test was used to compare the mean against the null hypothesis of random choice (alternative hypothesis is the mean being greater than the presumed probability of 0.33 for colour and 0.5 for odour and conflict). All statistic models are described in the R script below.
Files and variables
Software used: R.
File: Sensory_RScript_DDD.R
Description: R Script for statistical analysis. This file contains all the packages, statistical models and graphs used in the manuscript. It is divided per analysis in the same order as the published article. To use the script, you need to add the .xlsx tables below.
File: Sensory_fulldata2_DDD.xlsx
Description: This file contains raw data for statistical analysis. Each tab contains data from a different experiment:
Tabs
- Tab Pre_trial_results: This tab contains data from the naive colour choice experiment. Head: “Species” (name of the observed species); “Group” (group of individuals tested together); “Orange” (number of feeding attempts on orange flower); “Red” (number of feeding attempts on red flower); “Pink” (number of feeding attempts on pink flower); “Yellow” (number of feeding attempts on yellow flower); “Total” (total number of feeding attempts); “Orange_p” (proportion of feeding attempts on orange flower); “Red_p” (proportion of feeding attempts on red flower); “Pink_p” (proportion of feeding attempts on pink flower); “Yellow_p” (proportion of feeding attempts on yellow flower).
- Tab Colour: This tab contains data from the colour choice experiment. Head: “Species” (name of the observed species); “Group” (group of individuals tested together); “Day” (which day of the experiment, from 1 to 5), “Orange” (number of feeding attempts on orange flower); “Red” (number of feeding attempts on red flower); “Pink” (number of feeding attempts on pink flower); “Total” (total number of feeding attempts); “Orange_p” (proportion of feeding attempts on orange flower); “Red_p” (proportion of feeding attempts on red flower); “Pink_p” (proportion of feeding attempts on pink flower).
- Tab Odour: This tab contains data from the odour choice experiment. Head: “Species” (name of the observed species); “Group” (group of individuals tested together); “Day” (which day of the experiment, using sugar or water), “Orange” (number of feeding attempts on orange scent); “Grass” (number of feeding attempts on lemongrass scent); “Total” (total number of feeding attempts); “Orange_p” (proportion of feeding attempts on orange scent); “Grass_p” (proportion of feeding attempts on lemongrass scent).
- Tab Conflict: This tab contains data from the conflict experiment. Head: “Species” (name of the observed species); “Group” (group of individuals tested together); “Day” (which day of the experiment: naive, learn or swap), “Orange” (number of feeding attempts on orange flower); “Pink” (number of feeding attempts on pink flower); “Total” (total number of feeding attempts); “Orange_p” (proportion of feeding attempts on orange flower); “Pink_p” (proportion of feeding attempts on pink flower).
This data was collected by scoring observations of butterfly behaviour in common garden assays. The raw number and proportions of choices are provided in the full data set file. All statistical analysis are in the R scripts.
R Software required to open and run the R scripts.