The ability to taste bitter flavors probably didn't evolve as a self-defense mechanism

From beer to coffee, bitter flavors are things that most of us have to learn to enjoy over multiple tastings. Scientists have long assumed that our ability to even taste those flavors is rooted in self-defense — a way to root out and avoid potentially poisonous plants in the diet of our hunting and gathering ancestors. But new research suggests that the ability to taste bitter flavors isn't strongly tied to hunting and gathering lifestyles, which leaves researchers at a loss for why the skill might have evolved. My hypothesis, based on experience with espresso and IPA lovers: Perhaps there's an evolutionary advantage to beverage pretentiousness.