When you look at pictures of the Earth from space, what’s the first thing that you see? A blue marble, as some have described it. A water world where oceans and swirls of white clouds dominate. But most of us will then have our attention drawn to the shapes imprinted on its surface – the continents. And they come in many colors. The white of Antarctica, the beige of the Sahara, the light green of grasslands, and the darker shades of our planet’s forests in their many forms.