Neutrality in plant–herbivore interactions
Cite this dataset
Pan, Vincent; Wetzel, William (2024). Neutrality in plant–herbivore interactions [Dataset]. Dryad. https://doi.org/10.5061/dryad.qjq2bvqnz
Abstract
Understanding the distribution of herbivore damage among leaves and individual plants is a central goal of plant-herbivore biology. Commonly observed unequal patterns of herbivore damage have conventionally been attributed to the heterogeneity in plant quality or herbivore behavior or distribution. Meanwhile, the potential role of stochastic processes in structuring plant-herbivore interactions has been overlooked. Here, we show that based on simple first principle expectations from metabolic theory, random sampling of different sizes of herbivores from a regional pool is sufficient to explain patterns of variation in herbivore damage. This is despite making the neutral assumption that herbivory is caused by randomly feeding herbivores on identical and passive plants. We then compared its predictions against 765 datasets of herbivory on 496 species across 116° of latitude from the Herbivory Variability Network. Using only one free parameter, the estimated attack rate, our neutral model approximates the observed frequency distribution of herbivore damage among plants and especially among leaves very well. Our results suggest that neutral stochastic processes play a large and underappreciated role in natural variation in herbivory and may explain the low predictability of herbivory patterns. We argue that such prominence warrants its consideration as a powerful force in plant-herbivore interactions.
README: Neutrality in Plant–Herbivore Interactions
https://doi.org/10.5061/dryad.qjq2bvqnz
Description of the data and file structure
HV_data_cleaned_long.csv and HV_data_cleaned_short.csv
- surveyID: surveyID
- MAT: Mean annual temperature in C
- MAP: Mean annual precipitation in mm
- plantHeight_cm: plant height in cm
- numLeaves: number of leaves on a single plant
- plantID3.long: Unique plant ID
- Lat: plant latitude in degrees decimals
- Long: plant longitude in degrees decimals (some of the coordinates censored for protection of rare plants)
- percHerbPlant_EstimationMethod: did the survey follow HerbVar protocol? 'hvp' is the highest precision, followed by 'hv', and then the bin resolution
- PI: Principal investiger
- siteSimp: Site name
- leafID: Leaf ID
- percLf: Proportion herbivory on the leaf
- species: plant species
- genus: plant genus
- sp: plant species name
- family: plant family
- n.avg: median number of leaves within a survey
Sharing/Access information
Data was from the HerbVar Network (https://herbvar.org). While using the data is fair game, it is still recommended that one please consult the steering committee before using the data in a publication.
Code/Software
The code used for the simulations and analyses is available on Zenodo. The custom R package herbivar and a vignette on how to fit the neutral model to herbivory data are available on Zenodo as an archived version and as a maintained version via GitHub (https://github.com/vsbpan/herbivar).
herbivar_0.2.0.tar.gz This is the R package. Install with install.packages(PACKAGE_PATH, repos = NULL, type = "source")
Using_‘herbivar’_to_Fit_Neutral_Models.html This is the knitted vignette on how to fit the neutral model to herbivory data
manuscript_analysis.zip This zip file contains numberd scripts that should be run sequentially. The R scripts derive the model objects and perform calculations. The 6_main_manuscript_results.html and 6_main_manuscript_results.rmd display the reported manuscript results / figures.
Methods
The details can be found on the HerbVar website: https://herbvar.org/protocols.html and the supplement of Pan & Wetzel 2024.
Funding
National Science Foundation, Award: DEB-2203582