Data from: Defecation in preparation for ecdysis drives microplastic clearance in cricket nymphs
Data files
May 15, 2026 version files 121.82 KB
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Moulting_plastic_paper_datasets.xlsx
116.82 KB
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README.md
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Abstract
Plastic pollution is widespread in both terrestrial and marine environments, creating significant ecological concerns. Animals that occupy lower trophic levels, like many small insects, can ingest and retain plastics for extended periods before eliminating them. Ecdysis, or moulting, occurs in arthropods during development and facilitates growth, but its role in microplastic (MP) clearance, and whether it is impacted by MPs, are largely unexplored. We used the cricket Gryllodes sigillatus to examine how and when moulting influences MP clearance in a hemimetabolous species known to ingest and tolerate MPs throughout development. We tested two alternative hypotheses of how moulting influences MP clearance: (1) that moulting of the gut lining removes MPs, or (2) that cessation of feeding and/or purging frass before ecdysis occurs removes MPs. In doing so, we also provide new evidence that cricket nymphs exhibit a cyclical (cosinor) pattern of frass production associated with ecdysis. We found that the events leading to ecdysis likely act synergistically to clear the gut contents from crickets' digestive tracts, with the slowing and cessation of feeding and the clearance of frass from the digestive tract eliminating most MPs from the cricket’s gut before ecdysis. We also observed that the timing of ecdysis and overall frass production remained unaffected by continuous MP ingestion, whereas switching between MP and non-MP diets caused modest changes in the timing of frass production within an instar. Crickets are known to biofragment MPs into NPs, which, with gut-clearing, likely allows them to deposit plastic-laden frass rapidly and reduces the likelihood of upward trophic transfer by reducing MP retention.
Dataset DOI: 10.5061/dryad.mw6m906bf
Description of the data and file structure
Repeated measures of cricket frass production were taken every 6 hours, and the cricket frass was fed to 4 different diets. Some diets contained microplastics.
Files and variables
File: Moulting_plastic_paper_datasets.xlsx
Description: Sheet 1 is for Moulting crickets weeks 2-3 and Moulting crickets week 3-4. Sheet 2 is for Cosiner curve (instar 5). Sheet 3 is for Key times plastic presence.
'Moulting crickets weeks 2-3' is related to Table 1 for the nymphs containing microplastics. 'Moulting crickets weeks 3-4' is related to Table 1 for the nymphs containing microplastics. 'Cosiner curve (instar 5)' is for Figure 3, showing each instar 5 individual's frass weight, timing, and diet. 'Key times plastic presence' is related to Figure 4, for which frass was digested to determine whether it contained any microplastics at key time points.
The variable 'diet' has the conditions Control-Control, Control-MP, MP-Control, and MP-MP. The first diet is the feed given to crickets during their 4th instar; the second diet is the feed given during their 5th instar.
NA indicates when no measurement was taken for that individual. This is due to the individiual timing of moulting thus, measurments started when moulting occured and ended 6 hours after the next moulting.
Sheets 1 & 2: Moulting crickets weeks 2-3 and Moulting crickets week 3-4
| Variable | Description |
|---|---|
| id | cricket id |
| moulted | if moulting occurred (n for no, y for yes) |
| day | day of check after feeding occurred |
| weeks | week is the age of crickets (Time) |
| Particle number | particle number is value applied for each particle observed within that individual (sequential numbering) |
| Area | Area is the area of that unqiue plastic particle (micon squared; µm2) |
Sheet 3: Cosiner curve (instar 5)
| Variable | Description |
|---|---|
| id | cricket id |
| time | the vial id for each frass collection based on that individuals moulting timeline |
| hours | hour of which frass collection occurred as timing to M2 (instar 5) moult (Hours) |
| frass | weight of the frass present at that individuals time after M1 (Milligrams; mg) |
| m2 | when moulting into instar 6 (m2) occurred (n for no, y for yes) |
| diet | the diet to which the crickets were fed on (Control-Control, Control-MP, MP-Control, MP-MP) |
Sheet 4: Key times plastic presence
| Variable | Description |
|---|---|
| id | cricket id |
| point | that individual crickets key time. 6m1 being 6 hours after first moult, 48m1 being the peak for that individual, m2b is last frass present before moult 2, m2a is 6 hours after moult 2 |
| hour | the hour at which is was collected for each individual (Hours) |
| pres | pres is if plastic was found to be present within the frass (0 for no presence, 1 for present) |
| diet | diet is the feeding that cricket was exposed to (Control-Control, Control-MP, MP-Control, MP-MP) |
Code/software
N/A
