fraud and fakery—which the totally guileless Wallace, as thoroughly 
decent a human being as ever existed, was ill-equipped to perceive. 
Wallace’s gullibility in this matter greatly annoyed Darwin, and led 
to a rift between the two men that never completely healed. 
The irony, of course, is that both Wallace and Darwin were right. 
The problem is one of levels of analysis. No reasonable scientist 
doubts the central role played by natural selection in the evolution- 
ary process, normally at the level of the local population (Tattersall, 
1994). But, equally, it is evident that natural selection per se cannot 
be responsible for the emergence of the evolutionary novelties 
which it acts to promote or eliminate. A wholly different set of 
mechanisms, acting at the genomic and developmental levels, comes 
into play here, and at least potentially these mechanisms are totally 
independent of those that enter into the selective process. Darwin 
was certainly correct in surmising that natural selection played a 
crucial role in establishing enlarged and rewired brains in certain 
local populations of our ancestors (presumably on the basis of sub- 
stantial rather than marginal advantages conferred by the resulting 
behaviors, for the brain, as Bob Martin [1983] pointed out in his 
James Arthur lecture several years ago, is metabolically a very ex- 
pensive luxury). But Wallace was equally accurate in his belief that 
natural selection could not have created human consciousness—that 
it could not in itself have produced the reconformed or enlarged 
structures that are responsible for the human capacity, and that it 
was to favor once they had come into existence. For every organ- 
ismic attribute has to exist before it can acquire an identifiable func- 
tion. In this very limited sense all successful evolutionary novelties 
must necessarily arise as exaptations (Gould and Vrba, 1982): fea- 
tures that appear in one context (in this case, independently of ad- 
aptation) before being co-opted by selection in another. 
But the emergence of novelties and their fixation in local popu- 
lations via natural selection is not the whole evolutionary story. 
Local populations are reproductively compatible with other popu- 
lations of their species, and their unique characteristics are at risk 
of loss through intermixing and reabsorption at any time. Discrete 
historical identity is only conferred on populations by the very poor- 
ly understood event of speciation: an event caused by a process (or, 
