Yesterday's sea hare was not much more than a fist-sized blob of goo on the sand, but it was aware. If we touched it, it quivered in response, as if to signal "Put me back in the water, please!" Self aware? With only a few tens of thousands of neurons, presumably only in the most elementary sense. The sea hare's awareness is mostly focused on finding food and a mate. For food, seaweed (of the same color as itself!). For a mate -- well, another sea hare; they are hermaphroditic.
All sexual eukaryotes are aware of their environment; all must find food and mates, and escape predators. Specialized cells -- neurons -- make this possible. A human brain contains about 100 billion neurons; stretch out their axons end to end and they'd reach to the Moon. One hundred trillion synaptic connections. A human brain is the most complex thing we know about in the universe, and with it comes that mysterious thing called self-awareness. The apes may be self-aware, but in humans self-awareness has become a planet-transforming emergent quality. We are, whether we like it or not, the lords of creation -- at least in this little corner of the universe -- and with such awesome power comes a proportionate responsibility. To whom? We have no dictates from on high. We assume our own responsibilities. To ourselves. To each other. To sea hares.