Based on localization error for a single perisaccadic flash, eye position signal is supposed to change more slowly than physical eye position. Nevertheless, a flicker is not perceived as moving in accordance with localization error for a single flash. We carried out two experiments to investigate this problem. Experiment 1 examined how a single flash or a flicker presented before saccade was pe...

Hamilton's theory of kin selection is one of the most important advances in evolutionary biology since Darwin. Central to the kin-selection theory is the concept of inclusive fitness. However, despite the importance of inclusive fitness in evolutionary theory, empirical estimation of inclusive fitness has remained an elusive task. Using the concept of individual fitness, I present a method for ...