Herbivorous insects have evolved many mechanisms to overcome plant chemical defences, including detoxification and sequestration. Herbivores may also use toxic plants to reduce parasite infection. Plant toxins could directly interfere with parasites or could enhance endogenous immunity. Alternatively, plant toxins could favour down‐regulation of endogenous immunity by providing an alternative (exogenous) defence against parasitism. However, studies on genomewide transcriptomic responses to plant defences and the interplay between plant toxicity and parasite infection remain rare. Monarch butterflies (
Animals rely on a balance of endogenous and exogenous sources of immunity to mitigate parasite attack. Understanding how environmental context affects that balance is increasingly urgent under rapid environmental change. In herbivores, immunity is determined, in part, by phytochemistry which is plastic in response to environmental conditions. Monarch butterflies We investigated plant‐mediated influences of elevated CO2(eCO2) on endogenous immune responses of monarch larvae to infection by We fed monarchs two species of milkweed; The melanization response of late‐instar larvae was reduced on medicinal milkweed in comparison to non‐medicinal milkweed. Moreover, the endogenous immune responses of early‐instar larvae to infection by Animal populations face multiple threats induced by anthropogenic environmental change. Our results suggest that shifts in the balance between exogenous and endogenous sources of immunity to parasite attack may represent an underappreciated consequence of environmental change.
- NSF-PAR ID:
- 10452599
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Animal Ecology
- Volume:
- 90
- Issue:
- 3
- ISSN:
- 0021-8790
- Page Range / eLocation ID:
- p. 628-640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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