I did a lot to describe more carefully what biological species are. I made a more… I made a clear distinction now between the species as a concept and a species as taxon. I made a much better analysis of the process of speciation. In 1954 I had published a paper in which I showed that the usual description of speciation, namely the split of a widespread species through a newly arising geographical barrier was really a… a… the much rarer process of speciation. A more common one was that a species established a new founder population way beyond, or well beyond, the borders of the… the current borders of the species, and that this isolated founder population that had budded-off, so to speak, from the maternal species eventually could develop into a separate species. And in this 1954 paper I expanded this idea a great deal and I said that this fact that this founder population was established by just a few individuals with only very… a very small part of the genotype of the widespread highly variable maternal populations, permitted, if one allows for the interaction among genes, permitted the restructuring of the genotype and under the very strict selection of this founder population in a new environment there was a chance that something quite new could evolve in such a founder population. And I called this process ‘peripatetic speciation’. And I pointed out in the original paper that this would be an explanation of the phenomenon that Darwin had already emphasized, and every palaeontologist since, that new species in the fossil record always seem to turn up suddenly without any seeming connection to anything else. I said if you have a founder population and that evolves gradually, the chance that this will be found in the fossil record is virtually nil. It is only if such a population is highly successful and spreads widely, then all of a sudden it will turn up somewhere in the fossil record. And that very process that I describe, both in my ’54 paper and then again in my 1963 book, later on was picked up by Eldredge and Gould and, without them adding very much that is new, renamed as punctuated equilibria. And everybody who now talks about punctuated equilibria thinks this was invented by Eldredge and Gould, but Eldredge, in an earlier paper in 1971, gives me full credit for it, but the Eldredge Gould paper of 1972 fails to list the 1954 paper in their bibliography.