The mutation arose as breeders cultivated tomatoes to ripen evenly, a trait that makes harvesting cheaper and more efficient. As pretty as they look, though, mutated tomato fruits are less efficient at photosynthesizing, found a new study. As a result, they make less sugar and other compounds, which means they often taste far worse than tomatoes that may look blotchy but are full of explode-in-your-mouth sweetness.