I'm the universe. God, if you wish to call it that. The only thing that exists. You all are a part of me, as is the earth, the solar system and everything else. Which still doesn't mean I give a hippy shit about saving the trees or starving children.
Now, that was the easy part.
The hard thing about your question is really that of why the heck our consciousness is a local phenomenon, i.e. why you think that you are in your own body.
In my eyes, the body of animals has, through interconnectedness by neurons, achieved a certain degree of coupling in the fog of quantum uncertainty that is the universe. The information that enters at one point of the body is transferred to a central entity, the brain, quick enough before randomness destroys that information.
The thing that separates my consciousness from yours is that my information entirely depends on the signals gathered by the cells that make up my body. I think that conjoined twins (There is a famous case of two with one body and two heads) are capable of having a sense of identity as being one being, but that also humans have the ability to have two identities in one body (Such as is the case of multiple personality disorder).
So while being joined by neurons gives you the ability to have a single consciousness, it is no must.
Now, another question is of course that of superorganisms such as ants. I think that ants are rightfully regarded as a single organism and have an identity as a colony, but I doubt that they have a sense of consciousness as a single being. If they were to travel lightyears instead of a few centimetres, the information they carry back into the colony is certainly subject to quantum uncertainty. Thus, humans can have a social identity as being one, but I doubt they would be able to share a single consciousness as they are not physically connected (yet).
Now, if you are the universe itself, why do you have a consciousness at all? I mean, one would not expect the universe to have a consciousness.
The answer to that perhaps lies in the quantum mechanic nature of the world. Without anyone observing the universe, it is in all states simultaneously (Schrödinger's Cat, essentially). You are an observation of the universe, a state of the latter. In fact, every human being is a state on its own right, such as every animal and everything else. Quite obviously, the universe seems to prefer to be observed (A collapse of the wave function, if you may), as if it would not, we would just be some weird quantum fog. Going one step further, we perhaps can think of the universe liking to be maximally observed, i.e. the more information a certain state can observe, the more likely the universe is in that state. A single electron can observe a single bit of observation, spin up or spin down, thus its consciousness would be pretty limited. Undoubtedly, humans are the type of being on earth that has a maximal consciousness, thus being able to observe a lot of information at once, thus being a likely state of the universe to be in.
To summarize, if you are a state of the universe, you are likely to be a state that carries some maximal observation power, i.e. a human (or similar).
Lastly, while it holds for me that I am the universe, so does it hold for you. Your consciousness is also a valid state for the universe to be in, and you are your own universe in your own right.
Welcome to the Donariverse, bitches.