Steve Jones, the great Welsh geneticist, was here to talk about coral, the subject of his new book, but took a detour into bananas. Specifically, the banana on the video here which has apparently done the rounds on YouTube, but was - judging from the laughs - the first time most of us had seen it.
It seems to be an absurd pastiche but Jones claims that the intelligent design lobby do indeed believe that the five-sided, flip-top [sic] banana shows the work of a higher power, who wanted to faciliate the sliding of this gorgeous fruit from hand to gaping mouth.
As Jones explains, these banana lovers are starting from the wrong end, looking at what survives selection as predetermined. He pulls out a favourite Darwin quote: those who see organisms without the benefit of evolutionary theory view the natural world "as a savage looks at a ship" - a vast and complex object that must have been made by a god. Today, "the savages are still indeed looking". And while he points to the growth of creationism and intelligent design in the US as possibly the most widespread and alarming trend, he cautions of the impact of other religions, and cites a 2006 BBC poll showing that only 48% of Britons believe in evolution.
Proponents of design, he says, look at organisms that exist now and ignore the billions of things that never made it. Evolution can do things designers never could: he talks us through 45 generations of a nozzle that engineers produced by trial and error, ending with a complicated structure 100 times more efficient than the prototype - a structure that no physicist or mathematician's equation could yet explain.
He claims all scientists are pessimists and says we as a species have a gloomy future - but clearly has no truck with those who might offer any religious comfort: "a danger to civilisation". A vicar in the audience gets short shrift, and Jones warns that: "Religion is doing itself huge harm by taking on science in a battle it is bound to lose."
Later, I bump into Jones, who says the great thing about Hay is that he can give the same talk each year and just change the title. But with that title in mind, what of the coral? The arguments and parallels for evolutionary theory and the reef make up his book: but one small aside in his talk was that we humans share certain genes not only with chimpanzees but also flat worms, sea anemones and even the organisms that make coral. In other words, the extraordinary thought that on some level the reefs are made of the same stuff as those of us who go exploring them.
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