If you are able to step outside and hear many types of birds, you might also have a greater feeling of well-being. Two studies show that hearing diverse birdsongs may help increase our happiness. One study was done by researchers at California Polytechnic State University (Cal Poly, for short). A research team studied the effects of birdsong on people walking through a park in the U.S. state of Colorado. A biology graduate student, Danielle Ferraro, led the Cal Poly study. Ferraro says that there could an evolutionary reason why we like birdsong. “There could be, sort of, an evolutionary reason why we like birdsong so much. And the idea is that when we hear birdsong it could … signal safety to us.” There could be many other reasons too. Ferraro states that in some areas around the world birdsong can also signal the arrival of spring and nice weather. Bird diversity, she adds, can also mean a healthy environment. She explained her study to VOA. Ferraro and her team played recorded songs from a diverse group of birds native to the area. They did this on hiking trails in a park in Boulder, Colorado. Over several weeks, the researchers played recorded birdsong at certain times of the day and other times they did not. Then they talked with hikers after they passed by. Hikers who heard the recorded diverse birdsongs reported a greater sense of well-being than those who heard simply the natural birds. The researchers suggest that both the bird sounds and biodiversity can increase feelings of well-being.