Chemoecology
December 2008
Anting, the plumage-dipping behavior to which ants (mostly formicines) are commonly subjected by birds (mostly passerines), is shown in tests with hand-raised Blue Jays (Cyanocitta cristata) and the ant Formica exsectoides to be instinctive: the birds displayed typical renditions of the behavior on the first occasion that they encountered ants. Evidence is presented supportive of the view that anting is a strategy by which birds render ants fit for ingestion. Formicine ants are ordinarily protected by their formic acid-containing spray.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2008
In Lepidoptera, forewings and hindwings are mechanically coupled and flap in synchrony. Flight is anteromotoric, being driven primarily by action of the forewings. Here we report that lepidopterans can still fly when their hindwings are cut off, a procedure reducing their total wing surface, on average, by nearly one half.
View Article and Find Full Text PDFExtensive chemical analyses of spider venoms from many species have revealed complex mixtures of biologically active compounds, of which several have provided important leads for drug development. We have recently shown that NMR spectroscopy can be used advantageously for a direct structural characterization of the small-molecule content of such complex mixtures. Here, we report the application of this strategy to a larger-scale analysis of a collection of spider venoms representing >70 species, which, in combination with mass spectrometric analyses, allowed the identification of a wide range of known, and several previously undescribed, small molecules.
View Article and Find Full Text PDFBeetles of the family Lycidae have long been known to be chemically protected. We present evidence that North American species of the lycid genera Calopteron and Lycus are rejected by thrushes, wolf spiders, and orb-weaving spiders, and that they contain a systemic compound that could account, at least in part, for this unacceptability. This compound, a novel acetylenic acid that we named lycidic acid, proved actively deterrent in feeding tests with wolf spiders and coccinellid beetles.
View Article and Find Full Text PDFSeveral volatile compounds, including terpenoids, fatty alcohols, fatty acids and some of their esters, were identified from solvent extracts prepared from anal scent glands of nutria (a.k.a.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2006
Pinoresinol, a lignan of wide distribution in plants, is found to occur as a minor component in the defensive secretion produced by glandular hairs of caterpillars of the cabbage butterfly, Pieris rapae. The compound or a derivative is appropriated by the larva from its normal food plant (the cabbage, Brassica oleracea). Pinoresinol was shown to be absent from the secretion if the larva was given a cabbage-free diet but present in the effluent if that diet was supplemented with pinoresinol.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2005
The moth Utetheisa ornatrix (family Arctiidae) depends on pyrrolizidine alkaloids (PAs) for defense. It sequesters the toxins as a larva from its food plants (Crotalaria species: family Fabaceae) and retains them through metamorphosis. We report here that PA-possession in the adult female U.
View Article and Find Full Text PDFCapillary NMR spectroscopy (CapNMR) was used to characterize 13 new cardenolides and related steroids from a severely mass-limited natural products sample derived from a rare firefly, Lucidota atra. These analyses were carried out on only partially purified samples, each containing 20-100 mug of up to three steroids. Compared to other NMR spectroscopic techniques, CapNMR provided an up to 3-fold gain in sensitivity while maintaining very high spectral quality, which was essential for the identification of the L.
View Article and Find Full Text PDFPyrrolizidine alkaloid (PA), sequestered by the moth Utetheisa ornatrix from its larval food plant, is transmitted by both males and females to the eggs. Males confer PA on the female by seminal infusion, and females pass this gift, together with PA that they themselves procured as larvae, to the eggs. Here we show that PA protects the eggs against parasitization by the chalcidoid wasp, Trichogramma ostriniae.
View Article and Find Full Text PDFThe opilionid Acanthopachylus aculeatus was shown to produce a defensive secretion containing quinones (2,3-dimethyl-1,4-benzoquinone, 2,5-dimethyl-1,4-benzoquinone and 2,3,5-trimethyl-1,4-benzoquinone), confirming the findings reported nearly a half century ago in a classic study. The mechanism by which the opilionid puts the secretion to use is described. When disturbed, the animal regurgitates enteric fluid, which it conveys by intercoxal clefts to the anterolateral corners of the carapace, where the two gland openings are situated.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
November 2003
Females of the arctiid moth Utetheisa ornatrix mate preferentially with larger males, receiving both direct phenotypic and indirect genetic benefits. Here we demonstrate that the female's mating preference is inherited through the father rather than the mother, indicating that the preference gene or genes lie mostly or exclusively on the Z sex chromosome, which is strictly paternally inherited by daughters. Furthermore, we show that the preferred male trait and the female preference for that trait are correlated, as females with larger fathers have a stronger preference for larger males.
View Article and Find Full Text PDFLarvae of the European cabbage butterfly, Pieris rapae (Pieridae), are beset with glandular hairs, bearing droplets of a clear oily secretion at their tip. The fluid consists primarily of a series of chemically labile, unsaturated lipids, the mayolenes, which are derived from 11-hydroxylinolenic acid. In bioassays with the ant Crematogaster lineolata, the secretion was shown to be potently deterrent, indicating that the fluid plays a defensive role in nature.
View Article and Find Full Text PDFTo examine the chemical defense of lepidopteran eggs towards ant predators, eggs of the arctiid moth Utetheisa ornatrix were offered to laboratory colonies of the ant Leptothorax longispinosus. The ants rapidly devoured Utetheisa eggs produced by parents reared on an alkaloid-free diet, but left eggs that had been endowed with parental alkaloid largely unmolested. That defense can be attributed directly to the presence of a pyrrolizidine alkaloid since topical application of monocrotaline in either its free base or N-oxide state conferred protection on otherwise palatable eggs.
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