Some
Lithops, or living stones. Notice both the sphere shape, and the pretty "windows" on the top. These plants are like icebergs, with most of the plant underground. The windows allow sunlight to shine into the middle of the plant, where there is the wherewithal to photosynthesize. After rains they swell up, exposing the windows, which can then make and store food. During prolonged drought, the plant shrinks under the ground so as not to use up precious water. Here are several species, and you can imagine that the colors are designed to make the plant inconspicuous in various environments, i.e. to match the color of local rocks and soil.
