Pulse, By Robert Frenay

It's a hard, soft and wet life

The wheel is a great invention. It has been gamely employed in many forms of transport for thousands of years, from Egyptian chariots to the latest sports car. Yet nowhere in nature do we see animals using wheels to move around.

The glib reason is that there is no need for wheels in a natural world devoid of roads. A more sensible reason has to do with the difficulty of "designing" the technology of a wheel when there is no intelligent designer. Natural selection has proved a pretty effective force in the construction of beautifully elaborate structures. But it is dumb design based on trial and error and blind selection.

With natural selection you can only build a complex structure, such as an eye, from what has gone before. It is not intelligent design that can think its way out of a problem with the help of conscious foresight - the sort of skill needed to design and build a wheel.

But nature, or rather evolution, has designed many structures and materials that have defied human ingenuity. Take the case of spider silk. Weight for weight it is tougher than steel - a giant web made from finger-thick spider silk would stop a fighter jet in full flight. Because of its immense tensile strength, materials scientists have been trying to build synthetic versions of spider silk for years.

Robert Frenay sees the 21st century as the age when nature becomes an even greater inspiration for developments in fields such as materials science, nanotechnology and robotics. He envisages computers with emotions, ships that move like swimming fish and aircraft that can fly like swooping birds. Penguins can swim 130 kilometres on the fuel from just one kilogram of fish - the equivalent of using a litre of petrol to travel 1,500 km in water. If we could learn how nature accomplishes such feats of engineering and energy efficiency, it would be a lesson worth knowing.

Nature builds all its vast array of different structures, from the delicate wings of an insect to the massive oak tree, using less than a dozen basic materials. Humans, on the other hand, have devised many more kinds of materials. However, it is the economy yet infinite variety of nature's designs that puts us to shame.

The most obvious way of taking a leaf out of nature's book is to emulate living organisms completely: artificial life, or A-life. Frenay divides the field into "soft", "hard" and "wet", depending on whether it builds software models of life, the hardware of robots or, the ultimate feat, creating living cells from a soup of inert chemicals.

For some time, science has been moving closer to the "carbon-silicon" interface: the idea of connecting the silicon of computers to the carbon-based materials of the brain. A shadowy US funding organisation called the Defence Advanced Research Projects Agency, which figures frequently in Frenay's story, has spent millions on its Brain-Machine Interface Program.

This is an ambitious book that covers many different scientific disciplines. The title comes from the idea of a pulse as the heartbeat of life, as well as a seed for transmitting genetic information from one generation to the next - a distinguishing feature of life.

Frenay perhaps labours the metaphor a little too much - we hear about the pulsing stops on a river journey through a jungle, the information pulsing through a wire connected to a brain and even the beating pulse of a university campus. Part of the problem, I suspect, is in having to draw together disparate themes to formulate a unified whole. On balance, though, it has worked.

Steve Connor is The Independent's science editor