There are some tastes that we're hard-wired to favour. One of those is sweetness. Not only does an early preference for sweetness help to ensure that babies are attracted to the slightly sweet taste of breastmilk, but our general preference for sweetness is understood to be an evolutionary adaptation, motivating us to seek out and consume (once rare) energy- and carbohydrate-rich foods. Sweetness may also have become a signal for safety, as there are hardly any naturally sweet foods that are toxic.
The bumps on your tongue, called papillae,