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Abstract Parents can provide care to their offspring to increase their offspring's chance of survival. There are various types of parental care across insect taxa, one of which is maternal investment. Lipids, the most energy‐dense of macronutrients, are considered a good estimate of maternal investment in insects. However, it is not clear how different environments, such as host plants, can impact provisioning, especially for dietary generalists that feed on an array of plant species with varying quality. Using an extreme dietary generalist, fall webworm (FW,Hyphantria cunea), we investigated if females provision different amounts of lipids into their eggs depending on the diet they fed upon as larvae. We measured the lipid content of FW egg clusters from parents reared on seven host plant species of varying quality. We found that parental host plants influenced egg provisioning, such that provisioning depends on host plant but also increases most for parents reared on low‐quality diets. Additionally, we found that female parents with heavier pupal mass produced egg clusters with greater lipids per egg. Our results provide evidence that egg provisioning can depend on the parental environment and suggest that the use of low‐quality host plants by generalist herbivores may be partially overcome via maternal investment.
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This content will become publicly available on July 6, 2026
Examining the performance of an insect generalist reared on unused host plants in Colorado
Dietary generalist insects are important to ecological communities because they are commonly found in many environments and play important roles in ecosystem services like pollination and decomposition. Although dietary generalist herbivores eat a broad range of plant species, regional populations of these species may have significantly narrower or specialized diet breadths. Fall webworm (Hyphantria cunea, hereafter FW) is a dietary generalist at the species level, but we do not know if there is dietary generalism at the population level or how generalism varies across populations. In Colorado, FW larvae feed on only a few plant species, but many plant species are available that are used by FW elsewhere and not locally. We investigated if FW may be an example of a species that is a dietary generalist when considered over a large geographic range but is composed of populations with narrower diets regionally.We reared FW larvae from fifteen maternal lines in Colorado on a local high-quality host plant and compared their performance (survival, development time, and pupal mass) with larvae reared on plants that are not used locally. We found that FW performance was significantly reduced on plant species that Colorado FW does not use. Our findings demonstrate that Colorado FW cannot eat the same plants as FW in the eastern United States and thus lack the physiological ability to feed on these plants. Our research also suggests that FW are a generalist species with narrower diets that vary regionally at the population level.
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- Award ID(s):
- 2030743
- PAR ID:
- 10631674
- Editor(s):
- Doris, Nicole; Vahl, Cate; Kruger, Elijah
- Publisher / Repository:
- University_of_Denver
- Date Published:
- Journal Name:
- University of Denver Undergraduate Research Journal
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2690-4160
- Subject(s) / Keyword(s):
- diet breadth, dietary generalism, Erebidae, insect herbivore, Lepidoptera
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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