Tall person

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Even when sitting, tall people are better at judging distance

Whether spotting danger from across the desert or getting a good view at a concert, height has been an advantage for millennia. Now, new research suggests that how taller people learn to see the world helps them better judge distances in dark environments. When calculating the distance of an object, the human brain relies on cues learned over time to estimate depth. These cues can include the size of one object relative to others, how much texture the object appears to have, and the object’s perceived height from the ground. However, a dark room in which a person can see only the object removes many of the brain’s tools for judging distance. Researchers tested 24 people, split into two gender-equal groups of tall and short, by putting them in an unfamiliar, dark room with only dim red LED lights on the ground or the ceiling for reference. The subjects were shown a suspended Ping-Pong ball with an LED that flashed for 2 seconds. The Ping-Pong ball was then removed, and the subjects then had to walk across the room along a guide rope and indicate where they thought the ball had been. For the targets located more than 3 meters away, the taller subjects were better at accurately guessing the distance of the Ping-Pong ball, according to a study published today in the journal Science Advances. When the experiment was moved to a fully lit outdoor field, taller subjects were still better at guessing the distance of the Ping-Pong ball, even when they were made to sit and shorter subjects were allowed to stand. The researchers suspect that the tall advantage comes down to angle: The higher up a person’s eyes, the more easily they can look down and see the distance between two objects. With this additional information, a taller person’s brain creates a better internal map for processing distance that works—even when the lights don’t.