1. Life History Differences Between Lepidoptera Larvae and Blattodea Nymphs Lead to Different Energy Allocation Strategies and Cellular Qualities.
- Author
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Taheri, Fahimeh and Hou, Chen
- Subjects
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LIFE history theory , *LEPIDOPTERA , *BIOMASS , *CATERPILLARS , *WEIGHT loss - Abstract
Simple Summary: Lepidoptera species have higher growth rates than Blattodea species. The different growth rates lead to different strategies to allocate energy to biosynthesis and somatic maintenance under free-feeding and low-food-availability conditions. Moreover, Lepidoptera and Blattodea spend sharply different amounts of energy on synthesizing one unit of bio-tissue, which, in turn, leads to different cellular qualities and abilities to resist stress, and may have effect on their adult lifespan. Based on this evidence, we postulate that the capability of maintaining homeostasis not only depends on the amount of energy allocated to maintenance, but also depends on the quality of the tissue, and that the tissue quality is at least partially due to the energetic investments in biosynthesis. In short, materials that are cheap to synthesize deteriorate faster, and allocating more energy to biosynthesis enhances somatic maintenance. Different life histories result in different strategies to allocate energy in biosynthesis, including growth and reproduction, and somatic maintenance. One of the most notable life history differences between Lepidoptera and Blattodea species is that the former grow much faster than the latter, and during metamorphosis, a large amount of tissue in Lepidoptera species disintegrates. In this review, using Lepidoptera caterpillars and cockroach nymphs as examples, we show that, due to these differences in growth processes, cockroach nymphs spend 20 times more energy on synthesizing one unit of biomass (indirect cost of growth) than butterfly caterpillars. Because of the low indirect cost of growth in caterpillars, the fraction of metabolic energy allocated to growth is six times lower, and that for maintenance is seven times higher in caterpillars, compared to cockroach nymphs, despite caterpillar's higher growth rates. Moreover, due to the higher biosynthetic energy cost in cockroach nymphs, they have better cellular qualities, including higher proteasomal activity for protein quality control and higher resistance to oxidative stress. We also show that under food restriction conditions, the fraction of assimilated energy allocated to growth was reduced by 120% in cockroach nymphs, as they lost body weight under food restriction, while this reduction was only 14% in hornworms, and the body mass increased at a lower rate. Finaly, we discuss future research, especially the difference in adult lifespans associated with the energetic differences. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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