Question

How can the thickening of the epidermis loose less water

Answer 1

Where water is plentiful and temperatures are moderate, plants have wide, thin leaves with lots of surface area for maximum photosynthesis. Plants adapted to drought conditions, however, exhibit a number of structural features that prevent water loss, helping them survive hot, dry conditions. They also have physiological mechanisms that aren't directly observable and that help them conserve water. Many of these plants are suitable drought-tolerant landscaping subjects.