Data from: Colony discrimination and competition in the eusocial trematode, Himasthla rhigedana
Data files
Feb 22, 2024 version files 731.19 MB
Abstract
The California horn snail (Cerithideopsis californica) hosts a diverse community of trematode parasite species, yet these species rarely co-occur in the same host. Some trematodes in this community competitively exclude conspecifics and heterospecifics using a soldier caste. How these trematodes can distinguish colonymates from competitors is unknown. Here we examine patterns of colony discrimination in Himasthla rhigedana, a marsh-dwelling species of parasitic trematode that possesses a soldier caste in their intermediate snail hosts. Aggression assays pairing colonies against multiple opponents demonstrate that H. rhigedana distinguish between conspecific colonies, consistently directing more attacks towards colonies collected from a distant marsh. We demonstrate that conspecific interactions between colonies are predominantly symmetrical (both colonies attack during encounters), and that the likelihood of aggression is the same whether the attacker soldier is “sterile” (soldier redia with no germinal balls) or an “intermediate” (soldier redia with developing germinal balls). Recognizing heterospecific or conspecific threats is a necessary function for the evolution of soldier castes, which almost exclusively occur within eusocial insects. By finding parallels in disparate phyla, our results in H. rhigedana provide a foundation for understanding the evolution of colony discrimination generally, as well as in trematode species and other parasite taxa with similar competitive interactions.
README: Colony discrimination and competition in the eusocial trematode, Himasthla rhigedana
https://doi.org/10.5061/dryad.jh9w0vtjt
ONLINE RESOURCE 1 (.zip) ##################################################
Decription: A zip file of videos (.wmv) of cercariae collected from each colony used in our manuscript. Cercariae are how morphological species claims are made for our trematode species, so we include these videos as reference for how we identified each species used in our experiments. These videos comply with the CC0 license waiver required by Dryad for publication, and we allow any readers to make their own morphospecies claims as desired from these videos. Within the zip file is two folders, one for each assay (ABC, ABX). Each file name indicates the colony the cercariae were collected from. For example, "A1_Cercs_1.wmv" in the ABC folder shows the cercariae from colony A1 in the ABC assays.
ONLINE RESOURCE 2 (.txt) ##################################################
Description: A text file showing the final alignments of each COI sequence from the trematode colonies used in the ABC assays. This file is used in the accompanying R code to generate our haplotypes for Figure 4. More information on how these alignments were chosen can be found in the manuscript methods.
ONLINE RESOURCE 3 (.csv) ##################################################
Description: A csv dataset recording the aggressive interactions between trematodes in our ABC and ABX assays. This file was used in the accompanying R code to generate our boxplots and bar graphs for Figures 2 and 3, as well as the statistical tests using the binary attack outcomes as dependent variables in our pairwise t-tests (Table 1). All of these figures as well as the information found in our tables can be replicated by inputting this dataset into our R code and following the embedded instructions.
Explanation of data by column:
ASSAY = Categorical, binary. Indicates whether the sample in a row was used in the "ABC" or "ABX" assays described in the main manuscript.
TRIAL = Numerical, discrete. A trial is one set of an ABC or ABX assay, labelled in chronological order.
COLONY = Categorical, binary. Only "A" or "B" are possible. Indicates which colony, within an ABC or ABX assay, a soldier trematode was sampled from.
ENEMY = Categorical. Indicates which colony, within an ABC or ABX assay, a recipient trematode was sampled from.
TYPE = Categorical. An abbreviation that indicates the location and species sampled from the field. For example, "BL-Hirh" means a trematode samples from a Bolinas Lagoon snail host, identified as the morphospecies Himasthla rhigedana. More information about these abbreviations can be found in the main manuscript.
BITES = Numerical, discrete. The number of soldier worms that engaged in biting their paired recipient. This can be from witnessing a "bite" on camera, or by witnessing the devoured remains that suggest aggression/biting occured.
BITES.C = Numerical, discrete. The same data as the BITES column, but manually corrected, removing cases where the soldier trematode appeared to be biting or had previously consumed an enemy cercariae, not the enemy redia they were paired against. This is the column we call upon in our measurements of aggression.
ONLINE RESOURCE 4 (.csv) ##################################################
Description: A csv dataset used specifically for the logistic regression models (Table 2). All the information in table 2 can be replicated by inputting this dataset into our R code and following the embedded instructions. However, the table output provided by the stargazer package will be slightly different than what is observed in the manuscript (Table 2), as slight visual changes were made in latex before adding the table to the manuscript.
Explanation of data by column:
ASSAY = Categorical, binary. Indicates whether the sample in a row was used in the "ABC" or "ABX" assays described in the main manuscript.
TRIAL = Numerical, discrete. A trial is one set of an ABC or ABX assay, labelled in chronological order.
TREATMENT = Categorical, binary. Indicates what type of pairing the trematodes in the corresponding row were in, as well as the directionality of aggression. For example, "AB" means a soldier from colony A paired against a recipient from colony B.
COLONY = Categorical. Indicates the colony ID and what trial the colony was in. For example, "A1" is the "A" colony from Trial 1 of either the ABC or ABX assay. A1 can exist twice, one for ABC and one for ABX, but this does not confound the data, as only one assay type is called when each logistic regression model was generated in R.
ENEMY = Categorical, binary. Indicates which geographic region the recipient worm in an assay came from.
N.ENEMY = Numerical, binary. A dummy variable for the ENEMY column.
WELL ID = Numerical, discrete. Indicates which arena the trematode was assayed in. Every pairing had its own unique arena.
BITES = Numerical, discrete. The number of soldier worms that engaged in biting their paired recipient. This can be from witnessing a "bite" on camera, or by witnessing the devoured remains that suggest aggression/biting occured.
BITES.C = Numerical, discrete. The same data as the BITES column, but manually corrected, removing cases where the soldier trematode appeared to be biting or had previously consumed an enemy cercariae, not the enemy redia they were paired against. This is the column we call upon in our measurements of aggression.
GERMS = Numerical, discrete. The maximum number of germinal balls observed within soldiers on video.
COI-N = Numerical, discrete. The number of nucleotide base pair differences found between the two colonies paired in assay. Essentially the hamming distance between two sequences pulled, unaltered, from our "ONLINE RESOURCE 2" supplemental file.
COI-K80 = Numerical, continuous. The Kimura parameter distance between the COI sequences of the paired colonies. More information on this model of genetic distance measurement can be found in the main manuscript, in the documentation for the dist.dna function in R.
COI-TN93 = Numerical, continuous. Another version of the Kimura parameter distance between the COI sequences of paired colonies. More information on this model of genetic distance measurement can be found in the main manuscript, in the documentation for the dist.dna function in R.
ONLINE RESOURCE 5 (.R) ##################################################
Description = An R code file, allowing any reader to replicate the figures and tables and statistical results shown in the corresponding pre-printed manuscript. Instructions for how to upload data and output the figures and tables are included inside, but these instructions assume the reader already has a basic knowledge of using R. All relevant outputs for this code file are included in the supplemental materials of this Dryad submission.
Methods
Methodology can be found in the corresponding pre-printed manuscript.