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Updated: Aug 6, 2026
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Published on: May 31, 2018
Environment and Host Genetics Drive Infection Outcomes in a Butterfly Host, but Do Not Interact With Each Other
Ania A Majewska1,2, Grace Chlebove3, Jacobus C de Roode3
1Southeastern Cooperative Wildlife Disease Study, Department of Population Health College of Veterinary Medicine, University of Georgia Athens Georgia USA.
Ecology and Evolution
|August 5, 2026
Summary
Host genetics and larval food plants independently affect monarch butterfly parasite resistance and lifespan. No significant gene-environment interactions were found for infection outcomes in this study.
Area of Science:
- Ecology
- Evolutionary Biology
- Parasitology
Background:
- Host-parasite interactions are influenced by host genetics and environmental factors.
- Understanding these interactions is key to managing infectious diseases.
Purpose of the Study:
- To investigate how host genetics and larval food plant environment affect monarch butterfly (Danaus plexippus) resistance to Ophryocystis elektroscirrha.
- To determine the significance of genotype and environment (G × E) interactions on infection outcomes.
Main Methods:
- Utilized 31 full-sib families of monarch butterflies.
- Exposed larvae to two milkweed species (Asclepias curassavica and A. incarnata) as distinct environmental conditions.
- Inoculated butterflies with the protozoan parasite O. elektroscirrha.
- Assessed infection probability, burden, host lifespan, and size.
Main Results:
- Milkweed species significantly impacted infection status, infection burden, and host lifespan.
- Host genetics influenced lifespan and wing length.
- No significant G × E interactions were detected for any infection-related outcomes.
Conclusions:
- Larval diet and host genetics act independently in shaping monarch butterfly responses to O. elektroscirrha.
- Findings suggest separate genetic and environmental pathways influence parasite resistance and host fitness.
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