Alejandrino Pérez seems barely aware of the heat as the sun rises above our heads. One by one he proudly points out three water pans – small reservoirs – which the people of San Matías Chilazoa, here in Mexico’s Oaxaca Central Valley region, have created to collect and store rainwater, mostly for animals to drink.

These pans were an important development, as the village’s Zapotec Indigenous community live mainly from rearing sheep and goats and growing crops.