Six-month-olds’ pupils widen more for spiders than flowers in a controlled study

A tightly controlled study with 16 six-month-olds found spiders paired with color-matched flowers elicited greater pupil dilation than flowers alone, suggesting an early bias in attention/arousal to spiders. A second test with snakes vs. fish showed no difference, highlighting interpretive debates about whether this reflects prepared fear or other factors. Researchers caution that small sample size and potential image complexity limit conclusions and call for further work with constructed stimuli.