ClimateWire: Agave may be most associated with tequila, but this plant has a less familiar use -- it's teaching scientists about how to craft more drought-resistant plants. The hardy succulent, along with species like prickly pear (an edible cactus), pineapple and vanilla orchids, has evolved over millions of years to perform a different kind of photosynthesis that allows the plants to survive in semiarid environments where water isn't always readily available. The process is called crassulacean acid metabolism,...