The researchers studied how coffee plants react to bright sunlight. They found that one type of coffee plant needs more light to photosynthesize fully, has less chlorophyll, and recovers faster from sun damage than another type. They also discovered that a certain drug can speed up sun damage in one type of coffee plant and prevent recovery in both types. Overall, the coffee plants' ability to turn sunlight into energy was affected by the drug and bright light, but they could bounce back with time.