A TEASPOON AND AN OPEN MIND: The Science of Doctor Who by Michael White (Penguin/Allen Lane, £12.99)

TELEPORTATION - is it possible? For the makers of Star Trek, it had to be. Michael White explains: "The transporter was one of the mainstays of the programme and was put into the original show for the prosaic reason that the cost of landing a huge spaceship, the USS Enterprise was considered too great a drain on the special-effects' budget. To circumvent this problem, the creator of the show, Gene Roddenbury, came up with the ingenious idea of simply keeping the Enterprise in space and transporting the crew to the surface of an alien world whenever the need arose.''

But is it possible? Probably not. "For all the ingenious uses to which teleportation has been put in science fiction... using what we know of physical laws it would be rather difficult," admits White. "Indeed, it is no exaggeration to say that the idea of teleportation is one of the most far-fetched in all science fiction."

Author of biographies of Stephen Hawking, JR Tolkein and others, White gives serious scientific consideration to some of the ideas central to science fiction, particularly those encountered or exploited by Dr Who, who once identified "a teaspoon and an open mind" as his key tools.

What about extraterrestrial life? Could that exist, and if so what form might it take? White says: "To me, it seems ludicrous that in this vast universe we would be the only intelligent beings, and it strikes me to be supreme egotism to believe this." Because their bodies could use different chemicals to those found on Earth, and their planet's sun would probably emit different radiation, aliens could look green. But White's ultimate conclusion, that any intelligent beings elsewhere would be "at least vaguely similar to humans," will probably not satisfy fans of either Dr Who or Star Trek.

WHY BIRDS SING by David Rothenberg (Penguin/Allen Lane, £17.99)

IN 2000 David Rothenberg, an accomplished musician, began playing his clarinet among caged birds in America's National Aviary. Detecting a response, he began to investigate, through science, literature and his own further experiments, the great question of why birds sing.

Of our present habit of listening to birds, he says: "We often stop listening as soon as we identify what we cannot see darting through the trees." He wants to encourage people to "take a deeper listen", and help them interpret what they might hear. "Slow down these (the bird's) sounds," he says, "and you will hear much more nuance and structure. Print them out and they become complex rhythmic images."

Rothenberg has high praise for the 18th century peasant-poet John Clare, who rendered in verse what Rothenberg believes is the closest approximation in language to a nightingale's song. Having captured the phrases, he used them in several poems. "It is clear that he really listened to the birds as he worked the fields, seeking meaning in the rhythms," says Rothenberg.

While scientists and ornithologists tend to believe that birds sing only for practical reasons, like mating or claiming a territory, Rothenberg is convinced they sing simply for joy too. His own experiences suggest to him that human and bird collaboration is not impossible. "We should not dismiss the possibility that pleasure in song may be something that humans and birds can share."

Published: 07/03/2006