A study in the Journal of Evolutionary Psychology by Jeannette Haviland-Jones et. al. says that humans have cultivated flowers for more than 5000 years for not other reason than enjoyment. Given to women, they produce good moods for as many as three days later and even improve memory in older participants in the study. Both men and women show positive moods and more positive social behaviors and increase memory in both sexes. Why? The study suggests that flowers have evolved in their attraction characteristics not only to lure pollinators but to ensure we humans keep on gardening and cultivating.