del Campo Marta L, Smedley Scott R, Eisner Thomas
Department of Biological Sciences, State University of New York, Binghamton, NY 13902, USA.
Proc Natl Acad Sci U S A. 2005 Sep 20;102(38):13508-12. doi: 10.1073/pnas.0505725102. Epub 2005 Sep 8.
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. ornatrix has a life-shortening effect, suggesting that, by putting the compounds to use, the moth may be incurring a cost. However, PA-possession also induces the female to oviposit at an accelerated rate, so that she does not, by dying earlier, incur a loss in fecundity. We argue that by "compressing" their adult existence into a shorter period, female U. ornatrix may actually accrue benefits.
华丽金蛾(灯蛾科)依靠吡咯里西啶生物碱(PAs)进行自我防御。它在幼虫期从食物植物(猪屎豆属植物:豆科)中摄取这些毒素,并在变态过程中保留下来。我们在此报告,成年雌性华丽金蛾体内含有PAs会缩短其寿命,这表明,通过使用这些化合物,这种蛾子可能会付出代价。然而,体内含有PAs也会促使雌性加速产卵,这样一来,即使它过早死亡,也不会在繁殖力上有所损失。我们认为,通过将成年期“压缩”到更短的时间内,雌性华丽金蛾实际上可能会获得益处。