Dipartimento di Biologia, Università di Firenze, Via Madonna del Piano 6, 50019 Sesto Fiorentino (FI), Italy.
Dipartimento di Biologia, Università di Firenze, Via Madonna del Piano 6, 50019 Sesto Fiorentino (FI), Italy
J Exp Biol. 2018 Oct 15;221(Pt 20):jeb186247. doi: 10.1242/jeb.186247.
Communication through vibrational signals is widespread among social insects and regulates crucial social activities. Females of the social wasp produce substrate-borne vibrations on the combs by performing a conspicuous abdominal oscillatory behavior, known as abdominal wagging. Several studies have reported correlative evidence in support of its signaling role, but direct evidence is still lacking. Because abdominal wagging is strictly associated with the presence of larvae in the nest and with cell inspection, it has been suggested that it could be involved in adult-larvae communication. According to this hypothesis, abdominal wagging vibrations would have short-term effects related to food and trophallactic exchanges between adults and larvae by modulating salivary secretion (decreasing its amount, to prepare larvae to receive food, or stimulating the release of larval saliva to adults). Here, by using an electro-magnetic shaker, we assessed, for the first time, the short-term effects of abdominal wagging on larval behavior by recording larval responses and by measuring the amount of saliva released immediately after abdominal wagging playback. Our results show that larvae are able to perceive the substrate-borne vibrations produced by abdominal wagging and react by increasing the movement of their body, possibly in order to attract the attention of adult females during feeding nest inspection. Yet, we found that vibrations neither increase nor decrease the release of larval saliva. Our results support the hypothesis of the alleged role of vibrations in adult-larvae communications; however, they do not support the long-lasting hypothesis of salivary release modulation.
振动信号在社会性昆虫中广泛存在，调节着重要的社会活动。社会性黄蜂的雌性通过进行一种明显的腹部摆动行为，即在蜂巢上产生基质传播的振动，这种行为被称为腹部摇摆。已有几项研究报告了支持其信号作用的相关证据，但仍缺乏直接证据。由于腹部摇摆与巢中幼虫的存在以及细胞检查密切相关，因此有人认为它可能参与了成虫-幼虫之间的交流。根据这一假设，腹部摇摆振动会通过调节唾液分泌（减少唾液分泌量，为幼虫接受食物做准备，或刺激幼虫唾液向成虫释放）产生与食物和成虫-幼虫间营养交换相关的短期效应。在这里，我们首次通过使用电磁振动器来评估腹部摇摆对幼虫行为的短期影响，方法是记录幼虫的反应，并在腹部摇摆回放后立即测量唾液的释放量。我们的研究结果表明，幼虫能够感知到腹部摇摆产生的基质传播振动，并通过增加身体的运动来做出反应，可能是为了在喂食巢检查期间吸引雌性成虫的注意。然而，我们发现振动既不会增加也不会减少幼虫唾液的释放。我们的结果支持了关于振动在成虫-幼虫交流中的假设作用的假说，但不支持关于唾液释放调节的长期假说。
