Risk-sensitive foraging in a tropical lizard
Data files
Jan 22, 2025 version files 19.76 KB
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README.md
2.08 KB
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Supplement_1_Datasheet_Risk_sensitive_foraging.xlsx
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Abstract
Foraging opportunities can be unpredictable. When foragers face a choice between resources that vary in predictability, foraging decisions not only depend on the profitability of food but also on their physiological state. This risk-sensitive foraging approach, in which animals take greater foraging risks when starving, remains relatively untested in reptiles compared to other taxa. We tested the risk-sensitive foraging theory in the tropical lizard, Psammophilus dorsalis, by manipulating energy budgets (satiated vs. 48-hour starved) and measuring foraging preferences for options that differed in rewards: constant (2 mealworms) vs. variable (0 or 4 mealworms). We find that satiated lizards were risk averse to variability in reward amounts and chose the constant food option more frequently than the variable option. By contrast, starved lizards were risk prone and chose the variable reward option more often than the constant one. At the end of 28 foraging trials, these strategies resulted in both starved and satiated groups achieving similar net resource gains. As new support for risk-sensitive foraging in a tropical reptile species, these results provide insight on how resource uncertainty influences foraging strategies. For lizards in the tropics, which have high energy requirements year-round, risk-sensitive foraging could be an effective strategy in stochastic environments.
README
Title of dataset: Risk-sensitive foraging in a tropical lizard
Authors: Avik Banerjee1, Maria Thaker1
Affiliation: 1Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, India
The data files contains data on number of choices made, number of mealworms eaten and mass difference for both satiated and starved state lizards.
Description of the data and file structure
- "Supplement 1_Risk sensitive foraging_Datasheet" excel file: [Convert it to .csv file for use in the analyses with the R codes]. This excel file includes the following data:
Sheet 1
Column 1 consists of the lizard ID (or unique identifier).
Column 2 indicate the sex of the lizard ('F' for females and 'M' for males).
Column 3 indicate the starvation state of the lizard ('SATIATED' for satiated lizards and 'STARVED' for 48-hour starved lizards).
Column 4 indicates the choices available during the testing phase.
Column 5 indicates the number of times the choice in Column 4 was made during the testing phase.
Sheet 2
Column 1 consists of the lizard ID (or unique identifier).
Column 2 indicate the sex of the lizard ('F' for females and 'M' for males).
Column 3 indicate the starvation state of the lizard ('SATIATED' for satiated lizards and 'STARVED' for 48-hour starved lizards).
Column 4 and 5 indicates the initial (before experiment) and final (after experiment) Snout-Vent-Length (SVL, in mm) of the lizards respectively.
Column 6 indicates the total number of mealworms gained (count) as rewards during the testing phase.
Column 7 and 8 indicates the initial (before experiment) and final (after experiment) mass (in grams) of the lizards respectively.
Column 9 indicates the difference in mass (final mass - initial mass) (in grams) for lizards.
2. "Supplement 2_Risk sensitive foraging_Rcode.R" : includes all R codes with step-by-step comments to replicate the analyses.
3. A video named "Supplement 3_Risk sensitive foraging_Video" showing a male P. dorsalis lizard making a choice during the testing phase is provided.
Methods
We tested the risk-sensitive foraging theory in the tropical lizard Psammophilus dorsalis. We conducted a choice experiment with adult lizards of both sexes. In the experiment phase, lizards were subjected to different starvation treatment (satiated vs 48-hour starved). Morphometric measurments such as snout-vent length and body mass were measured before and after the experiment phase. During the experiment phase, lizards were also tested for their foraging choice between two food options which provided variable rewards (constant vs. variable number of mealworms).