Speculations on the origin of life have, until recently, been purely theoretical. …

• (Introduction)
• It's a small world
• Test tube evolution
• Links in a chain
• Looking for the right path
• The world that time forgot
• Merger or takeover
• Box 1
• Box 2

Biology Articles » Evolutionary Biology » Origin of Life » It's alive – isn't it? » Box 2

Box 2

- It's alive – isn't it?

2. Building life with clay

The idea of clay having a major role in the origin of life was first popularised by the British chemist Graham Cairns-Smith, who suggested that clay may have been the first genetic system. His theory was that irregularities in clay sheets could have acted as catalytic surfaces, as well as providing a template on which new clay could be added. The clay would 'reproduce' by splitting in two, with the new sheet retaining many of the old sheet's irregularities.

At some stage, however, carbon compounds would have become involved, and eventually RNA strands capable of self-catalysis would have been produced, as James Ferris is currently showing experimentally (see main text).