
Urban Birds Startle More at Women Than Men, Study Finds
An international study of 37 urban bird species across five European countries found birds let male researchers approach about three feet closer before fleeing than female researchers, a robust sex-based difference in flight initiation distance across cities and species. Researchers ruled out obvious factors like hair length, body size, and height, and suggested possibilities such as subtle appearance cues or odor, but no definitive explanation yet. The finding is consistent but remains puzzling to scientists.