Of course, we all know the answer to that one, don't we...
We know that plants don't have a nervous system, but they do respond to light. Light causes chemical changes in many plants causing them to react: opening/closing petals or just following the sun. I also note that if you "wound" many types of trees and shrubs and then bind the wound in moist compost, the plant responds by producing roots.
I'm sure others can find many more examples.
There's a point to all this (Dawkins may already have raised it, I don't know) - the eye is nowhere near as unique as creationists would have people believe.
(There are many types of eye that have evolved over the years in the animal and insect kingdoms but this isn't the point here).
Although our eyes are the product of millions of years of evolution, the actual process that works them (chemical changes in cells due to the interaction with light) has not altered that much. My understanding is that persistence of vision (the wonderful effect that allows us to enjoy movies) is largely due to the "slow" reactions of the chemistry involved.
Now, if we know that vision is the result of a chemical reaction and that a plant also responds to a light using a photo-reactive chemical change, it's not a huge jump to note the fundamental connection and another demonstration that evolution created us.