Animals often use assessment signals to communicate information about their quality to a variety of receivers, including potential mates, competitors, and predators. But what maintains reliable signaling and prevents signalers from signaling a better quality than they actually have? Previous work has shown that reliable signaling can be maintained if signalers pay fitness costs for signaling at different intensities and these costs are greater for lower quality individuals than higher quality ones. Models supporting this idea typically assume that continuous variation in signal intensity is perceived as such by receivers. In many organisms, however, receivers have threshold responses to signals, in which they respond to a signal if it is above a threshold value and do not respond if the signal is below the threshold value. Here, we use both analytical and individual‐based models to investigate how such threshold responses affect the reliability of assessment signals. We show that reliable signaling systems can break down when receivers have an invariant threshold response, but reliable signaling can be rescued if there is variation among receivers in the location of their threshold boundary. Our models provide an important step toward understanding signal evolution when receivers have threshold responses to continuous signal variation.

中文翻译：

---

阈值评估、分类感知和可靠信号的演变

动物经常使用评估信号将有关其质量的信息传达给各种接收者，包括潜在的配偶、竞争者和捕食者。但是，是什么保持了可靠的信号传输并阻止信号发送者发出比实际质量更好的信号？以前的工作表明，如果信号员为不同强度的信号支付健身成本，则可以保持可靠的信号传输，并且这些成本对于低质量个人来说比高质量个人更高。支持这一想法的模型通常假设接收器会感知到信号强度的连续变化。然而，在许多生物体中，接收器对信号具有阈值响应，其中如果信号高于阈值则它们响应，如果信号低于阈值则不响应。这里，我们使用分析模型和基于个体的模型来研究此类阈值响应如何影响评估信号的可靠性。我们表明，当接收器具有不变的阈值响应时，可靠的信令系统可能会崩溃，但如果接收器的阈值边界位置发生变化，则可以挽救可靠的信令。当接收器对连续信号变化有阈值响应时，我们的模型为理解信号演变提供了重要的一步。但是，如果接收器的阈值边界位置存在变化，则可以挽救可靠的信令。当接收器对连续信号变化有阈值响应时，我们的模型为理解信号演变提供了重要的一步。但是，如果接收器的阈值边界位置存在差异，则可以挽救可靠的信令。当接收器对连续信号变化有阈值响应时，我们的模型为理解信号演变提供了重要的一步。