Life is started by being self aware and able to reflect on one's actions and the actions of others. Plants have life, the grow, they breath and they react to pain. Even though they cannot talk like we do, they do talk to each other along their root systems. Dogs and cats and other animals have consciousness and they can think, feel and so on. I used to be able to understand what my cats thought. Even though I can't now, I know they have thoughts. I can even tell with they are talking to each other.