Sir

In the famous photographs of James Watson and Francis Crick with their DNA model (reproduced in Nature 421, 15 ; 2003 and Nature 421, 416; 2003) a small icon of information technology can be seen in Crick's right hand — a slide rule. (One wonders, incidentally, why this was shown in the photograph instead of the “measuring stick” which, together with a plumb line, they used “to obtain the relative positions of all atoms”, as described by Watson in The Double Helix — anecdote has it that Crick told the insistent photographer that the slide rule was irrelevant.)

At Newcastle University we have been teaching biology students the use of computers for nearly three decades, beginning each year with a brief account of the staggering advances in computational power since the middle of the twentieth century. Each year, we show them an example of what Crick held. It seems fitting, on the fiftieth anniversary of the reconstruction of DNA, and at the advent of the rise of computational biology (C. Surridge Nature 420, 205; 2002), to report that this year, for the first time, none of our first-year students recognizes a slide rule.