Nutritional condition or personality: what drives web investment in Cryptachaea migrans (Theridiidae)?

Data associated with the manuscript: Nutritional condition or personality: what drives web investment in Cryptachaea migrans (Theridiidae)? # GENERAL INFORMATION ## 1. Paper Citation Authors, 2026. Nutritional condition or personality: what drives web investment in Cryptachaea migrans (Theridiidae)? XXXXX, XXXXX. https://doi.org/XXXXX ## 2. Brief abstract Optimal Foraging Theory (OFT) predicts that animals adjust their foraging strategies to maximize energy gain. However, OFT rarely accounts for the effects of individual traits, such as nutritional condition and personality, on foraging decisions. Both nutritional condition and personality can shape behavioural decisions during foraging by modulating the level of risk individuals are willing to accept in relation to potential energetic benefits. Variation among individuals, including differences in condition and personality, makes trap-building animals, such as spiders, suitable models for investigating the relationship between risk and energy gain. In this study, we tested whether web-building investment in the spider Cryptachaea migrans (Theridiidae) is driven by nutritional condition or by personality traits related to boldness. We found that spiders with lower body fat proportions invested more in adhesive threads, whereas no relationship was detected between thread number and individual boldness. These findings suggest that individuals in poorer nutritional condition increase their foraging investment, possibly as a strategy to enhance prey capture and compensate for energetic deficits. Furthermore, both shy and bold individuals occasionally adopted strategies that resulted in energetically suboptimal decisions, incurring costs and risks disproportionate to expected returns, contrary to OFT predictions. Overall, our results indicate that individual variation, particularly nutritional condition, may play a more prominent role than personality in shaping foraging investment. This study highlights the importance of incorporating individual heterogeneity into theoretical frameworks of foraging, contributing to a more realistic understanding of behavioral strategies in natural systems. ## 3. Originators ## 4. Contact information ## 5. Date of data collection The data collection took between September and November of 2023 ## 6. Geographic location(s) of data collection Recanto das Cigarras, Federal University of Viçosa, Minas Gerais, Brazil ## 7. Information about funding sources that supported the collection and curation of the data GES and IMD was supported by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) (GES: xxxx; IMD: DS-88887.968052/2024-00). TGK was supported by the Fundação de Amparo à Pesquisa do Estado de Minas Gerais (FAPEMIG) (process APQ-00935–18). # ACCESS INFORMATION ## Licenses/restrictions placed on the data Creative Commons Attribution 4.0 International # DATA FILES AND VARIABLES This repository contains the data files: * Data_BCI_C_migrans.csv * Data_Boldness_C_migrans.csv ## 1. Data_BCI_C_migrans.csv These file contains data related to measurements of fat and web of Cryptachea migrans spiders. Variables:* ID: Identifier of each observation (replicate) (categorical) * Adhesive_threads: Number of adhesive threads in each observation (integer) * Dry_weight_1: Dry Weight of spiders on the first measurement (numerical) * Dry_weight_2: Dry Weight of spiders on the second measurement (numerical) * Fat: Fat weight after the second dry mass measurement of the spiders ## 2. Data_Boldness_C_migrans.csv These file contains data related to measurements of boldness and webs of Cryptachea migrans spiders. Variables: * ID: Identifier of each observation (replicate) (categorical) * Date: Date of each observation (categorical) * Adhesive_threads: Number of adhesive threads in each observation (integer) * Imobility_time: Recorded time during which the spider remained motionless in seconds (numerical) * Mean_displacement_time: Average travel time of the spiders across the three days of measurement, in seconds (numerical) * Mean_adhesive_threads: Average across the three days of measurement of the number of adhesive threads placed by the spider (integer) * sd_displacement_time: Standard deviation of Mean_displacement_time * Inverse_sd_displacement: Inverse of standard deviation of Mean_displacement_time # SOFTWARE VERSIONS All statistical analyses were conducted in R software, version 4.5.0. loaded packages: * package: DHARMa (v. 0.4.7)* package: rptR (v. 0.9.23) # NOTES All variables are described using consistent terminology to facilitate reuse. Missing values (if present) are indicated directly in the dataset files. For methodological details, refer to the main manuscript.