If an alien visited Earth, they would take some note of humans, but probably spend most of their time trying to understand the dominant form of life on our planet - microorganisms like bacteria and viruses.

If you find diseases before they've really emerged, you can control them early on, before you get a major epidemic.

If an alien visited Earth, they would take some note of humans, but probably spend most of their time trying to understand the dominant form of life on our planet - microorganisms like bacteria and viruses.

Don't assume that what we currently think is out there is the full story. Go after the dark matter, in whatever field you choose to explore.

We may have charted all the continents on the planet, and we may have discovered all the mammals, but that doesn't mean that there's nothing left to explore on Earth.

About 20 percent of the genetic information in your nose doesn't match anything that we've ever seen before.

We know there are certain types of viruses that are nasty - influenza, for instance, is an area that is not a blindside. But a lot of viruses have come out of nowhere, like H.I.V., or to a certain extent SARS. Because we know we have the potential to be blindsided, we really have to investigate the unknowns.