The other day I noticed a weed growing next to one of my tomatoes. It was almost identical to the tomato- little green berries and flowers. The giveaway was that the flowers were white, not yellow and the leaves were slightly different, but not much! It's not the first time I've noticed weeds looking like the plants they're growing next to. Is this just coincidence, or is there really a type of weed that exists that can adapt in this way?