Is it ethical to eat plants?

Plants may not squeal out in pain, but they're more like animals than you think.  When you look at time-lapse photography, plants do almost just about everything that animals do.  Perhaps the ethical case for eating plants isn't so clear cut.  From the NYT:

Unlike a lowing, running cow, a plant’s reactions to attack are much harder for us to detect. But just like a chicken running around without its head, the body of a corn plant torn from the soil or sliced into pieces struggles to save itself, just as vigorously and just as uselessly, if much less obviously to the human ear and eye.

When a plant is wounded, its body immediately kicks into protection mode. It releases a bouquet of volatile chemicals, which in some cases have been shown to induce neighboring plants to pre-emptively step up their own chemical defenses and in other cases to lure in predators of the beasts that may be causing the damage to the plants. Inside the plant, repair systems are engaged and defenses are mounted, the molecular details of which scientists are still working out, but which involve signaling molecules coursing through the body to rally the cellular troops, even the enlisting of the genome itself, which begins churning out defense-related proteins.

Plants don’t just react to attacks, though. They stand forever at the ready. Witness the endless thorns, stinging hairs and deadly poisons with which they are armed. If all this effort doesn’t look like an organism trying to survive, then I’m not sure what would. Plants are not the inert pantries of sustenance we might wish them to be.

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Human beings survive by eating other living things. I really want not only to eat, but to survive. Yet a nakedly logical way to judge the value of one kind of organism over another — the rightness of a plant’s death versus an animal’s — seems, to me, out of reach.