Ponies Aren’t Baby Horses, Pineapples Don’t Grow on Trees, and ‘Casualty’ Doesn’t Mean Dead: Users Are Sharing the Common Facts They Discovered Embarrassingly Late

Reddit users recently admitted in a viral thread that ponies are not baby horses, pineapples do not grow on trees, and several other facts they had accepted for years turned out to be wrong. Thanks to a Reddit post that asked: “What’s a ‘common knowledge’ fact that you genuinely had no idea about?” Below it, users shared facts they said they only discovered well into adulthood.

One of the most popular revelations was a Reddit user saying they were in their 20s before they realized ponies are not young horses. Another joked, “TIL ponies are baby horses,” while others struggled with the correction. In reality, ponies are characterized by their mature height rather than their age. The University of Florida’s Institute of Food and Agricultural Sciences says ponies are horses that stand under 14.2 hands at the withers. To make sense of this measurement, one has to know that one hand equals 4 inches.

Another Redditor said they were shocked to discover that pineapples grow on the ground, not on trees. Yes, the tropical fruit grows from a low plant with a rosette of long, pointed leaves, which is why the familiar supermarket fruit looks very different in its natural setting.

The thread mentioned also one of summer’s most recognizable sounds. One user recalled as a child that the buzzing of cicadas actually came from the sun because cartoons often paired the sound with shots of hot, bright weather. However, the Smithsonian Science Education Center states that male cicadas produce their characteristic sounds using structures called tymbals on their abdomen to attract females.

There were also practical discoveries, like one Redditor who said they only recently noticed that the small arrow next to a car’s fuel icon indicates which side of the vehicle the gas tank is on. Similarly, another user recently realized that a quart is one-fourth of a gallon.

The discussion also included childbirth, as one user said they were seven months pregnant when they learned that vaginal bleeding can continue for weeks after delivery. That is not the same as a period. The National Institutes of Health says postpartum bleeding and discharge, known as lochia, is normal after birth. Heavy bleeding, however, can lead to hemorrhage and needs medical attention immediately.

Other revelations were linguistic; for example, “casualty” does not necessarily mean someone died. One commenter also found out a biological fact that a groundhog and a woodchuck are the same animal.

The thread remained active as of publication, with users continuing to add their own long-held misconceptions.