@Alex Read "The Secret Life of Plants" and you will realize that plants might be self-aware too, so there is no point in trying to not cause harm to other lifeforms besides your own kind, unless you want to die.
@Alex Humans can petition for their rights. Animals cannot.
Murray Rothbard made that distinction in The Ethics of Liberty.
@Alex They can still communicate via mouthing. They can blink their eyes in Morse code or in binary.