Many herbivorous insects have specific host–plant preferences, and it is unclear how these preferences evolved. Previously, we found that Bicyclus anynana larvae can learn to prefer novel food odors from eating leaves with those odors and transmit those learned preferences to the next generation. It is uncertain whether such acquired odor preferences can increase across generations of repeated odor feeding and be maintained even in the absence of odor. In this study, we fed larvae with novel banana odor-coated leaves (odor-fed larvae) for five consecutive generations, without selection on behavioral choices, and measured how larval innate preferences changed over time. Then, we removed the odor stimulus from a larval subgroup, while the other group continued to be odor-fed. Our results show that larvae learned to prefer the novel odor within a generation of odor feeding and transmitted the learned preference to the next generation, as previously found. Odor-fed larvae preferred odor significantly more compared to control larvae across five generations of repeated odor or control feeding. However, this led neither to increased odor preference, nor its stabilization. This suggests that when butterfly larvae feed on a new host, a preference for that novel food plant may develop and be transmitted to the next generation, but this preference lasts for a single generation and disappears once the odor stimulus is removed.

中文翻译：

---

经过多代气味取食后，双环蝴蝶幼虫对新食物气味的后天偏好并没有变得更强或稳定

许多草食性昆虫具有特定的寄主植物偏好，目前尚不清楚这些偏好是如何进化的。此前，我们发现Bicyclus anynana幼虫可以通过吃带有气味的叶子来学习更喜欢新奇的食物气味，并将这些习得的偏好传递给下一代。目前还不确定这种后天获得的气味偏好是否会在几代人的重复气味喂养中增加，并且即使在没有气味的情况下也能保持不变。在这项研究中，我们连续五代用新型香蕉气味涂层叶子（气味喂养幼虫）喂养幼虫，不选择行为选择，并测量幼虫先天偏好如何随时间变化。然后，我们去除了幼虫亚群的气味刺激，而另一组继续接受气味喂养。我们的结果表明，正如之前所发现的，幼虫在一代气味喂养中学会了更喜欢新的气味，并将学到的偏好传递给下一代。在重复气味或对照喂养的五代中，与对照幼虫相比，气味喂养的幼虫明显更喜欢气味。然而，这既没有导致气味偏好的增加，也没有导致其稳定。这表明，当蝴蝶幼虫以新宿主为食时，对这种新食用植物的偏好可能会发展并传递给下一代，但这种偏好会持续一代，一旦气味刺激消失就会消失。