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better than others in the eyes of natural selection, and this meaning, these advantages, must almost always appear in bodies. These might not be the body that the gene itself is found in – the plant genes that control the colours of flowers, and make them attractive to bees, are really selected because of the way that bees’ eyes work. That was the argument of Richard Dawkins’s second, technical book, The Extended Phenotype. This seems to prove that you can reduce almost everything about evolution to genes. However, as Gould points out, gene-centrism reached a kind of reductio ad absurdum with the the discovery of “selfish” or “junk” DNA. This is the name given to bits of chromosomes, possibly proper genes, which are copied by the exuberance of the cell’s own copying mechanisms for no reason at all so far as the organism is concerned. These are genes which really are directly selected for their own physical qualities, not for their effects on the physical qualities of the cells that surround them. Their existence shows that normal DNA is selected in a more complicated way. The point at issue is really a confusion between copying and winnowing: selection is a two-stage process, endlessly repeated. Things are copied, then their copies are winnowed to select ones with certain qualities, and the survivors are copied again. But in genetic systems, copying and winnowing are separate process (except in the specialised case of junk or selfish DNA): the things that are copied – the genes – are not the things that are winnowed – the bodies. Neither the copying nor the winnowing can sensibly be called “selection” on its own. Nonetheless, it makes sense to ask what sorts of things are winnowed, and here Gould does go out on a limb. He argues that not merely individual bodies, but populations, whole species, and even clades – related groups of species – can compete with each other in a Darwinian sense, and so become the objects of selection. This idea brings together two of his constant themes, for he argues that adaptation at one level of the hierarchy is what produces the spandrels at the next level that provide the raw material for further adaptation in their turn. That would explain, for example, how the duplication of genes when they are copied into junk DNA, which is a product of purely molecular selection, nonetheless supplies the raw material or spandrels for natural selection to work on the organism. It is not at all clear how much this would revolutionise biology, nor how Gould might reconcile this kind of multi-level selectionism with his other belief that much evolutionary change is essentially random. It was a consistent complaint of Gould’s opponents that he oversold his own ideas. But he did have an enormous amount to oversell, and it is saddening to reflect that he will never now write more, or less.