DOI: 10.5281/zenodo.17021102
title: Family life and cadmium ingestion independently shape offspring microbiomes in a subsocial insect

description: READ ME

This repositery contains all dataset that allow to reproduce this study (16S rRNA sequences in .fastq format, the R script and the informative file related with the samples (env_succession.txt). It also contains Supplemental material to complete the related manuscript.

1) The file "cd_data.txt" 

It contains the informations regarding the samples. The description of the variables follows:



ID: The identifiant of the sample (host)

Clutch: The name of the family

Treatment: The cadmium doses that had been administered (0, 25 or 100 mg/L)

Group_nymph: social environment of the nymph where nymph are either isolated, with sibling (10 nymphs) or in family (10 nymphs with their mother).


2) The file "Cadmium_script.R" 

This script allows to perform all the bioinformatical process and analyses that were made for this study. It was made on R version 4.4. This script needs the source code provided by the "make_biom.R" code that will need to be downloaded in the "reference_database" the script creates (but see the Cadmium_script).

3) The RData objects

We publish the R objects (phyloseq objects) that allow to perform all statistical analyses from the initial object "ps_proka.RData" or directly after the core calculation "core.RData". It avoids to perform all bioinformatical steps to process the sequences.

4) The file "R1R2.zip"

This folder zip contains all sequence at fastq format. These sequences are from the V3-V4 of the 16S rRNA genes sequenced by Illumina MiSeq 2x250 bp.

5) The file "Supplemental Material.pdf"

This document contains all supplemental tables and figures related with our study. Specifically,



Table S1: Results of the DESeq2 analysis regarding the effects of the cadmium ingestion and the social environment.

Figure S1: Electrophoresis gel (agarose 1.5%) of the 16S rRNA amplicons.

Figure S2: Species-Abundance Distribution (SAD) patterns for the microbial ASVs of the European earwig nymphs.

Figure S3: Rarefaction curves for each nymph microbiome, depending on its social environment.

Figure S4: Alpha and beta-diversity of the nymph microbiomes.
description: Symbiotic microbes are essential for host health and fitness. In family-living species, these microbes are often acquired through vertical transmission from parents and horizontal transmission from siblings. However, it is unclear how environmental stressors, such as chemical pollution, influence these contributions to the juvenile microbiome. Here, we tested the independent and interactive effects of social environment and cadmium ingestion - a highly toxic and common heavy metal pollutant - on the microbiome of juvenile European earwigs. We reared 900 juveniles either alone, with siblings or with siblings plus the mother. We exposed them to cadmium-enriched food at 0, 25 or 100mg.L-1, and analysed their microbiome composition and diversity at the end of the family life period. Our results showed that both social environment and cadmium exposure shaped the juvenile microbial community composition (phylogenetic beta-diversity), with no evidence of an interaction between these factors. In contrast, the microbial local richness (alpha-diversity) remained unaffected by either factor or their interaction. Notably, several specific bacterial taxa, including putatively pathogenic (Serratia) and mutualistic (Lactobacillus) symbionts, were more abundant in juveniles reared with family members than in those reared in isolation, reflecting classical patterns observed  in social species. Overall, our findings suggest that while both social environment and cadmium shape the microbiome of earwig juveniles, family life neither amplifies nor mitigates the effects of chemical exposure. This highlights the robustness of microbial sharing within families, even under strong environmental stress.