In this July 21, 2016 photo, fireflies light up in sync in the woods of Piedra Canteada, near Nanacamilpa, Tlaxcala state, Mexico. The income from tourism is providing a new incentive to residents to focus on conservation rather than deforestation. In addition, Mexico's forest service is supporting the replanting of hundreds of thousands of trees in the area, and Piedra Canteada's Rueda Lopez said they have plans to plant over 50 thousand pine trees in the areas that they log each year. (AP Photo/Rebecca Blackwell)

Mexican farmers using fireflies to save forest

Inside the story: Photos

In the village of Nanacamilpa, tiny fireflies are helping save the towering pine and fir trees on the outskirts of the megalopolis of Mexico…