Genetic variation in parasite avoidance, yet no evidence for constitutive fitness costs

Behavioral avoidance of parasites is a widespread strategy among animal hosts and in human public health. Avoidance has repercussions for both individual and population-level infection risk. Although most cases of parasite avoidance are viewed as adaptive, there is little evidence that the basic assumptions of evolution by natural selection are met. This study addresses this gap by testing whether there is a heritable variation in parasite avoidance behavior. We quantified behavioral avoidance of the bacterial parasite Serratia marcescens for 12 strains of the nematode host Caenorhabditis elegans. We found that these strains varied in their magnitude of avoidance, and we estimated the broad-sense heritability of this behavior to be in the range of 11-26%. We then asked whether avoidance carries a constitutive fitness cost. We did not find evidence of one. Rather, strains with higher avoidance had higher fitness, measured by population growth rate. Together, these results direct future t..., , , # Genetic variation in parasite avoidance, yet no evidence for constitutive fitness costs

[https://doi.org/10.5061/dryad.1jwstqk2m](https://doi.org/10.5061/dryad.1jwstqk2m)

## Description of the data and file structure

The datasets and code in this repository accompany \"Genetic variation in avoidance, yet no evidence for constitutive costs,\" by Caroline R. Amoroso, Leila L. Shepard, and Amanda K. Gibson.

In the Data folder are two files:

**1. \"Lawn-leaving assay.csv\":** the original data collected for this project on the parasite avoidance behavior of *C. elegans* strains. Explanations of column headers:

Block: experimental block, 1 through 6

Plate_number: replicate plate

Bacterial_strain: OP50 (*E. coli* control) or Db10 (*S. marcescens* parasite)

C.elegans_strain: Code corresponding to one of 12 of the *C. elegans* strains from the CaeNDR \"divergent set\"\" (see [https://caendr.org/request-strains/](https://caendr.org/request-strains/))

Date_time_picked: Date and time that *C....