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If anything, we tend to picture matches as the earlier, more analog tool and lighters as a later convenience, but in fact lighters came first. In 1772, in Japan, Gennai Hiraga invented a lighter. Matches were invented later, in 1826, by the British pharmacist John Walker.

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You often see salmon fillets at the supermarket, right? Salmon is a familiar fish at the dinner table, and since its flesh is a beautiful reddish orange, you might assume it’s a red-fleshed fish—but in fact, it’s a white-fleshed fish. Whether a fish is classified as red or white is determined by the amount of pigment proteins.

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Not for soothing people by looking at them, but because every bank places a houseplant about 170 centimeters tall. The reason is that if a bank robber or suspicious person shows up, they can use it to get a rough idea of the person’s height.

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Salt and sugar are often seen as opposites, so you might think a slug would stretch out limply with sugar, but just like with salt, it shrivels up when sugar is applied. Since a slug’s body is mostly water, it shrinks due to the osmotic effect of salt, and sugar causes the same osmotic shrinking.

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You might think there’s no way connecting the blood vessels of such a small body would add up to a trip around the Earth, right? In fact, it would be more than two trips around the Earth! One lap around the Earth is about 4 km, while the total length of the blood vessels in the human body is said to be about 10 km.

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Avocados, which are often eaten in salads, might seem like vegetables, but they’re actually fruit. There are also things many people think are fruit that are in fact vegetables. Also, it’s often misspelled as “abogado,” but the correct spelling is “avocado.”

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It’s said that Type A is the most common blood type among Japanese people, but Types B, O, and AB also exist, and the distribution of blood types varies around the world. In Central and South America, Type O is overwhelmingly common, and in Colombia and Venezuela, everyone is Type O.