The earth's biosphere could be thought of as a sort of palace. The continents are rooms in the palace; islands are smaller rooms. Each room has its own decor and unique inhabitants; many of the rooms have been sealed off for millions of years. The doors in the palace have been flung open, and the walls are coming down.

As life forms, viruses are just inherently interesting. It's the microworld - this universe of life too small for us to see - but it's profoundly complicated, and immensely powerful. Ebola is like a beautiful and frightening predator. There is a wonder in the operations of nature that can't be denied, even when we're the losers.

Redwood time moves at a more stately pace than human time. To us, when we look at a redwood tree, it seems to be motionless and still, and yet redwoods are constantly in motion, moving upward into space, articulating themselves and filling redwood space over redwood time, over thousands of years.

First Light' is nonfiction, a true story about astronomers who are looking for light coming from the edge of the universe. It tells how science is really done - and science is a lot weirder and more human than most people realize.

Knowing that we are primates, I think, is a fascinating discovery, and a very interesting and rather cheering one.

With something like Chernobyl, the public reaction was 'Oh, my God, science has really done wrong.'

I love physics.

Philosophy was once considered science.