Just so you'll know for future reference, God has made a very clear distinction in the Bible between plants, animals and man. The Hebrew words describing their creation are different, as well as describing how they "die." In short, plants were given by God as food for man and animals. They don't figure into the effect of sin at all, unless you consider that God punished Adam and all his descendants with the burden of having to toil by the sweat of his brow to till the soil and struggle to produce food from the fall on.
You can read an article about it at:
If you pursue this study farther, you'll realize that not only are plants clearly different from animals, but animals are clearly very different from man. Man is unique in God's creation, and that's why no matter how "religiously" materialistic scientists try to produce man from mud, they'll never be able to do more than wander aimlessly around a maze of evolutionistic false trails.
Actually, you didn't answer my question. Now, I know it's not an easy one, but quite interesting; many other life-forms indulge in activities that we consider sinful in humans.