Birds can’t taste them. Deer avoid them. It seems that humans are the only animals on Earth who have a love of red, hot chili peppers. But how is it that humans evolved a liking for hot spices when the rest of the animal kingdom avoids it like the hot plague? Recently, the New York Times took a look at how this happened, as well as the psychology behind eating hot spices.

Chili peppers began making their way around the human diet as early as 7500 BC. There is archeological evidence that chili were cultivated in South and Central America. Christopher Columbus brought the first chilies to the old world and was the first to call them peppers, as they resembled the white peppers indigenous to Europe. Adding flavor to food at this time was so extravagant that some countries used black peppercorn as a currency. Soon chilies had made their mark on India, Central Asia, Turkey, Hungary and the world.

As the NY Times points out, some experts say we reach for the hot sauce because of its inherent health effects. Chili peppers can lower blood pressure. They are also an excellent source of vitamin C, vitamin B, potassium and iron. Some research shows that the pain of chilies can kill other pain. Capsaicin, the active ingredient in peppers, produces a burning sensation in any animal tissue it touches. So when a person eats chili, he is experiencing the same sensation as if his tongue was on fire. Experts think capsaicin may have evolved in plants to protect them against fungi because it is anti-microbial.

But others say these health benefits are not enough to explain why some people love chilies while others don't. Dr. Paul Rozin at the University of Pennsylvania is an expert on human likes and dislikes and author of “How Pleasure Works: The New Science of Why We Like What We Like.” As he told the NY Times, “I don’t think they [the health benefits] have anything to do with why people eat and like it.” But Rozin is quick to add, “This is a theory. I don’t know that this is true.”

Instead, Rozin says the rate at which people consume chilies has more to do with “benign masochism.” His research shows that people rate the level just below unbearable as the most pleasurable amounts of chili they can consume. In places like India and South America, hot peppers are part of the daily cuisine. But in America, there is a capsaicin following that involves T-shirts, clubs, and the hottest hot sauce you can find. Experts say this originates from a primal need to chest thump.

Ultimately, as Rozin explains, we are the only animals who can enjoy painful feelings because we realize they are actually not a threat. And consequently, only the animal with the “biggest brain, most intricate mind and weird self-awareness” can enjoy chilies.