Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
PLoS One. 2010 Sep 30;5(9):e13114. doi: 10.1371/journal.pone.0013114.
Predator attraction to prey social signals can force prey to trade-off the social imperatives to communicate against the profound effect of predation on their future fitness. These tradeoffs underlie theories on the design and evolution of conspecific signalling systems and have received much attention in visual and acoustic signalling modes. Yet while most territorial mammals communicate using olfactory signals and olfactory hunting is widespread in predators, evidence for the attraction of predators to prey olfactory signals under field conditions is lacking.
METHODOLOGY/PRINCIPAL FINDINGS: To redress this fundamental issue, we examined the attraction of free-roaming predators to discrete patches of scents collected from groups of two and six adult, male house mice, Mus domesticus, which primarily communicate through olfaction. Olfactorily-hunting predators were rapidly attracted to mouse scent signals, visiting mouse scented locations sooner, and in greater number, than control locations. There were no effects of signal concentration on predator attraction to their prey's signals.
CONCLUSIONS/SIGNIFICANCE: This implies that communication will be costly if conspecific receivers and eavesdropping predators are simultaneously attracted to a signal. Significantly, our results also suggest that receivers may be at greater risk of predation when communicating than signallers, as receivers must visit risky patches of scent to perform their half of the communication equation, while signallers need not.
掠食者对猎物社交信号的吸引力可能迫使猎物在交流的社交必要性和捕食对其未来适应度的深远影响之间进行权衡。这些权衡是同物种信号系统设计和进化理论的基础，在视觉和听觉信号模式中受到了广泛关注。然而，尽管大多数有领地的哺乳动物使用嗅觉信号进行交流，而且嗅觉捕猎在捕食者中很普遍，但在野外条件下，掠食者对猎物嗅觉信号的吸引力的证据却很少。
方法/主要发现：为了解决这个基本问题，我们研究了自由 roaming 的掠食者对从两组和六组成年雄性家鼠（Mus domesticus）收集的离散气味斑块的吸引力，这些家鼠主要通过嗅觉进行交流。嗅觉捕猎的掠食者很快就被老鼠的气味信号吸引过来，比控制地点更早、更多地访问有老鼠气味的地方。信号浓度对掠食者对猎物信号的吸引力没有影响。
结论/意义：这意味着如果同种接受者和偷听的掠食者同时被一个信号吸引，那么通讯将是昂贵的。重要的是，我们的结果还表明，与信号发送者相比，当进行通讯时，接收者可能面临更大的捕食风险，因为接收者必须访问有风险的气味斑块来完成通讯的一半，而信号发送者则不必。
