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Abstract In parasitoid systems, resource competition can significantly impact developmental outcomes. This study investigates how larval competition and host characteristics influence development in the acoustic parasitoid fly Ormia ochracea, using the house cricket Acheta domesticus as a host. We experimentally manipulated larval load (1 vs. 2 larvae per host) and recorded host sex and size to assess their effects on pupation and eclosion (adult hatching) success, as well as pupal and adult fly size. While double infestations increased total yield (0.78 vs. 0.54 flies per host), larvae developing without competition exhibited higher relative pupation and eclosion success and produced larger pupae and adult flies, indicating greater individual fitness. Although female host crickets yielded larger pupae, resource competition was the dominant factor shaping developmental outcomes. These results highlight the trade-offs between reproductive yield and offspring fitness driven by resource competition and validate the commercially available A. domesticus as a viable host.
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Identifying the proximal cue(s) for pupal color variation in the bordered patch butterfly, Chlosyne lacinia (Lepidoptera: Nymphalidae)
Abstract Coloration is a multifaceted trait that serves various functions, including predator defense, thermoregulation, and immune response, among others. We investigated pupal color variation in Chlosyne lacinia pupae, focusing on identifying the cue that influences variation in melanization. Through laboratory experiments, we demonstrated that pupae reared on black backgrounds exhibited significantly higher melanization compared to those on white backgrounds. Additionally, black pupae experienced longer developmental periods, suggesting a trade-off between defense and developmental time. Our findings support crypsis as a likely evolutionary driver for increased melanization in response to substrate color. We discuss potential implications for predator avoidance, immune response, and developmental costs associated with melanization. This study provides insights into the adaptive significance of pupal melanization in response to environmental cues, shedding light on the complex interplay between life history traits in butterflies.
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- Award ID(s):
- 2208922
- PAR ID:
- 10550172
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Annals of the Entomological Society of America
- Volume:
- 117
- Issue:
- 6
- ISSN:
- 0013-8746
- Format(s):
- Medium: X Size: p. 323-331
- Size(s):
- p. 323-331
- Sponsoring Org:
- National Science Foundation
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