Plants deserve more credit. They can't move to find food or water, or to escape a predator. But that doesn't mean they are helpless — far from it. They don't have eyes, ears, a nose or mouth, but they can sense the world remarkably well — in some cases better than we can.

For example, as you might expect, plants are highly sensitive to light. Humans have three different kinds of light-receptors in their eyes to sense light; plants have 15. Plants can monitor light levels very precisely, from the ultraviolet to the infrared.

Plants' powers of communication are also extraordinary. A plant being eaten by a predator such as a caterpillar will release ethylene, and this warns other plants that there is a threat nearby. If you look at a tree infested by herbivores and nearby trees that are untouched, you'll find that the uneaten trees have produced protective chemicals that render them unpalatable to predators.