The predominance of polyunsaturated fatty acids in the butterfly Morpho peleides before and after metamorphosis

Abstract

We hypothesized that the polyunsaturated fatty acids of the butterfly were probably derived from the diet and that there might be a great loss of body fat during metamorphosis. To substantiate these hypotheses, we analyzed the fatty acid composition and content of the diet, the larva, and the butterfly Morpho peleides. Both the diet and the tissues of the larva and butterfly had a high concentration of polyunsaturated fatty acids. In the diet, linolenic acid accounted for 19% and linoleic acid for 8% of total fatty acids. In the larva, almost 60% of the total fatty acids were polyunsaturated: linolenic acid predominated at 42% of total fatty acids, and linoleic acid was at 17%. In the butterfly, linolenic acid represented 36% and linoleic acid represented 11% of total fatty acids. The larva had a much higher total fatty acid content than the butterfly (20.2 vs. 6.9 mg). Our data indicate that the transformation from larva to butterfly during metamorphosis drastically decreased the total fatty acid content. There was bioenhancement of polyunsaturated fatty acids from the diet to the larva and butterfly. Insects and vertebrates share many common metabolic pathways. Although lipid metabolism in vertebrates has been well studied, there are fewer studies in insects. Insects may be useful models that can facilitate our general understanding of biology (1). For most insects, there is a dietary requirement for polyunsaturated fatty acids (2, 3). Using an analysis of the fatty acid composition of seven insect orders, Thompson (4) identified possible phylogenetic trends. It was also observed that in the order Lepidoptera, most of the species had a high content of polyunsaturated fatty acids. The linolenic acid of the 49 species analyzed varied from 0.1% to 51.0% of total fatty acids, with a mean of 22.2%. These trends provided insights into potential relationships between insect orders. The fatty acid composition of many insect species has been analyzed in the past (5, 6). However, in view of the multitude of insect species that exist, most knowledge of the fatty acid compositions of insects is derived from studies of a relatively small number of insect species.The butterfly of the order Lepidoptera undergoes metamorphosis from larva to butterfly. The larva feed on the leaves of the plants and then spin a cocoon. The butterfly feeds on flower nectar, which is available later in the year. We found no information about the fatty acid composition and fat content of the butterfly before and after metamorphosis and no information about how the diet of the larva might influence its fatty acid composition.On a recent trip, we visited the Butterfly Farm at Chaa Creek, Belize, in Central America. Chaa Creek is a tourist attraction and hostel for travelers in Belize. As we have developed an interest in the evolutionary patterns of fatty acids, having previously studied snails and slugs (7), we saw the potentialities of butterfly research and discussed our ideas with the scientific director, Mike Green. We decided to collab...

Effects of adult nutrition on female reproduction in a fruit-feeding butterfly: The role of fruit decay and dietary lipids

“…We here provided adult female butterflies with a mixture of linoleic acid, linolenic acid, arachidonic acid and eicosapentaenoic acid. Linoleic and linolenic acids are the most abundant PUFAs found in caterpillars and adult butterflies (Wang et al, 2006), and both are thought to adequately satisfy the nutritional need for PUFAs in most species and references therein). Further, they are considered essential fatty acids for many insect species (Beenakkers et al, 1985).…”

Energetic loads and informational entropy during insect metamorphosis: Measuring structural variability and self-organization

“…Furthermore, this 'U-shaped' pattern is correlated to a higher oxygen consumption as well as to the needs in lipids during the first stages of metamorphosis. On the other hand, species store lipid just before adult eclosion as an energy store for the forthcoming needs of flight (D'Costa and Birt, 1966;Law, 1980;Peakin et al, 1989;Nation, 2002;Nestel et al, 2004;Wang et al, 2006;Papanastastasiou et al, in press).…”

Effects of diet and metamorphosis upon the sterol composition of the butterfly Morpho peleides

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