An Evaluation of the Role of Sensory Drive in the Evolution of Lake Malawi Cichlid Fishes

Figure 8

Illustrative cartoon of the effects of sensory plasticity on multimodal male courtship signals. In all panels, the male signal is indicated by the black circle and the female “choice zone” (i.e., the male signal that will elicit a positive response) for three individuals are indicated via colored circles. In the case of a nonplastic species (a), a static male signal will likely overlap the choice criteria for all females, and even a small expansion of male behavior through plasticity will result in effective stimulation of all females involved (b). However, in the case of a plastic species with highly distributed female preferences, a static male signal is unlikely to overlap many female choice zones (c). In order to overlap the choice zones for multiple females, a male must therefore employ a very plastic signal to increase his odds of eliciting a positive response from a given female (d).