Like a lot of Americans, millions of monarch butterflies spend their winters in Mexico. Trouble is, the Mexican government has been unable to protect the monarch’s forest habitat from illegal logging. Reasoning that illegal logging stems from necessity — the 200,000-odd largely impoverished people who live in the Monarch Butterfly Biosphere Reserve clear the lands to grow crops, build their homes, and fuel their stoves — a Mexican nonprofit organization called Alternare has begun a quiet revolution to teach farmers sustainable living techniques in the name of the butterfly. The group teaches farmers to build from adobe rather than wood, to farm without chemical fertilizers, and to rotate crops for increased land productivity. Once farmers master the techniques, they teach them to others, and so Alternare’s vision is slowly spreading through the Mexican forest. With monarch habitat disappearing at alarming rates, critics fear the change is coming too slowly, but advocates say that for the first time, the interests of both the human beings and the butterflies in the area are being served.