On the Cover: The cover of this issue of Science Editor is a “photomacrograph of a close-up view of the pupil and iris in a human eye.” The size of the pupil (black) is controlled by the iris (bluish white) in reaction to stimuli, including light, physical activity, and emotional reactions. Pupil dilation can be useful in detecting artificial intelligence–based replicants via the Voight-Kampff test (at least according to Blade Runner).

Credit: Human eye with blue iris. Macroscopic Solutions. Source: Wellcome Collection. (CC BY-NC 4.0)