An evolutionary battleground: Plants vs. microbes

Gazing out on a freshwater pond, you may see tiny green plants with oval-shaped leaves floating in clusters. In overgrown ponds, these plants coat the water's surface. These plants—called duckweed or water lentils—can grow so fast that they can double their numbers in just one to two days. But what you can't see in that pond is the evolutionary battle between the plants and microbes trying to invade them.