The Nature of Plants

Plants and animals are very different kinds of living things, and this is because they have evolved different solutions to a single basic challenge: how to obtain the energy and substance necessary to grow and reproduce. Plants essentially nourish themselves. They build their tissues out of water, minerals, and air, and run them on the energy in sunlight. Animals, on the other hand, can’t extract energy and construct complex molecules from such primitive materials. They must obtain them premade, and they do so by consuming other living things. Plants are independent autotrophs, while animals are parasitic heterotrophs. (Parasitism may not sound especially admirable, but without it there would be no need to eat and so none of the pleasures of eating and cooking!)