European Great Tits and 36 other bird species on the continent are more afraid of women than they are of men, according to a recent study—and researchers have no idea why. In the study, men could get about a meter closer to birds than women could before the animals flew away, according to the results. This pattern remained regardless of what the men and women were wearing, what their height was or how they tried to approach the creatures. That suggests birds may be able to suss out the sex of a human, though the researchers aren’t sure how. “I...