We may be sucking in all sorts of viruses and we really don't know the full range of them. Maybe we've got flu virus inside of us. That's a possibility. Maybe we're part flu.

One of the big challenges now is to figure out just how many viruses there really are in the human genome. So far the estimate is 8.3% of our genome is virus, but it actually could be a lot higher.

There is some research that suggests that viruses like the flu are really actually kind of at the razor's edge when it comes to mutation. They're mutating so fast that if they mutated much faster they would actually develop a lot of harmful mutations that could slow them down and cripple them and eventually literally drive them extinct.

Viruses don't just make us sick. They can actually sometimes end up in our genomes.

If you're looking for your own idea of your own identity you know the human genome may not be the best place to look for it. You're just looking at a bunch of viruses.

Today, when we look at a brain, we see an intricate network of billions of neurons in constant, crackling communication, a chemical labyrinth that senses the world outside and within, produces love and sorrow, keeps our hearts beating and lungs breathing, composes our thoughts, and constructs our consciousness.

The only kinds of ways we have to deal with viruses are old school, so vaccines for example are very effective, but the first vaccines were invented in the 1700's, so we're talking about technology that is over 200 years-old.