FILE - In this Nov. 30, 2010 file photo, Mayan Indian Pedro Chuc May collects sap from a tree known as a gum tree to produce natural chewing gum in Betania, Mexico.  A U.N. program, under debate at the climate change conference in Cancun, could help May and millions of others who live in forests earn more while slowing the deforestation that accounts for one-fifth of the global carbon dioxide emissions blamed for warming the planet.  (AP Photo/Eduardo Verdugo, File)

Photo by: Eduardo Verdugo

FILE - In this Nov. 30, 2010 file photo, Mayan Indian Pedro Chuc May collects sap from a tree known as a gum tree to produce natural chewing gum in Betania, Mexico. A U.N. program, under debate at the climate change conference in Cancun, could help May and millions of others who live in forests earn more while slowing the deforestation that accounts for one-fifth of the global carbon dioxide emissions blamed for warming the planet. (AP Photo/Eduardo Verdugo, File)