Do fungi look like macroparasites? Quantifying the patterns and mechanisms of aggregation for host-fungal parasite relationships

Most hosts contain few parasites, whereas few hosts contain many. This pattern, known as aggregation, is well-documented in macroparasites where parasite intensity distribution among hosts affects host-parasite dynamics. Infection intensity also drives fungal disease dynamics, but we lack a basic understanding of host-fungal aggregation patterns, how they compare to macroparasites, and if they reflect biological processes. To begin addressing these gaps, we characterized aggregation of the fungal pathogen Batrachochytrium dendrobatidis (Bd) in amphibian hosts. Utilizing the slope of Taylor’s Power Law, we found Bd intensity distributions were more aggregated than many macroparasites, conforming closely to lognormal distributions. We observed that Bd aggregation patterns are strongly correlated with known biological processes operating in amphibian populations, such as epizoological phase (i.e., invasion, post-invasion, and enzootic), and intensity-dependent disease mortality. Using inte..., This dataset contains records of aggregated populations of amphibians and their fungal pathogen Batrachochytrium dendrobatidis (Bd) loads or intensities. Bd infection intensity obtained from amphibian skin swabs collected in the field. Bd loads were obtained through DNA extraction and qPCR, which detects the number of genomic equivalents or ITS1 copy number of Bd on amphibian skin. These methods were standardized across four dataset utilized for this study and published elsewhere. These included data taken from sites in São Paulo, Brazil [1; and manuscript in review], the East Bay region [2] and Sierra Nevada Mountains [3;4] in California, and across four states in the Eastern US [5]. Samples within each dataset were grouped based on host species, life stage (larva (i.e., tadpole in anuran species), subadult, or adult), research site, season (Brazil: Wet or Dry; East Bay and Sierra: Summer; Eastern US: winter, spring, summer, or fall), and year. 

Martins RA, Greenspan SE, Medina D, But..., , # Do fungi look like macroparasites? Quantifying the patterns and mechanisms of aggregation for host-fungal parasite relationships

[https://doi.org/10.5061/dryad.mgqnk998g](https://doi.org/10.5061/dryad.mgqnk998g)

## Description of the data and file structure

* Repository of code and data for the manuscript \"Do fungi look like macroparasites? Quantifying the patterns and mechanisms of aggregation for host-fungal parasite relationships\".

### Files and variables

#### File: abund\_and\_prev.csv

**Description:** Contains records of Sierra sites over multiple years and includes information on amphibian abundance, Bd prevalence, mean fungal load, and Poulin's D. Fields with a value of NA are defined as \"**Not Available**\" and indicates unknown or unrecorded data.

##### Variables

* site_id: (numeric) unique identifier for specific sampling sites
* year: (numeric) year in which samples were collected
* capture_life_stage: (character) life stage of grouped amphibians sampled (three level...