I wrote a new foreword for the new printing of a book dealing with the workshops I held in 1975 on the evolutionary synthesis. And in this new foreword I point out that many historians had confused what actually amounted to two different syntheses, the one taking place from 1916 to 1932 or ’35, and the other one taking place between 1937 and 1947. Now the first of these syntheses was within the field of genetics. The geneticists who, prior to that, as so-called Mendelians, believed in jumping, saltational evolution, mutationism as it is often called. They thought that by big mutations new species originated. And the next generation of geneticists, beginning with RA Fisher, [JBS] Haldane, Sewall Wright, [Hermann] Muller and many others, agreed that the genetic changes were not as… as big as claimed by the early Mendelians, but could be extremely small changes and leading to a gradual change to a continuous evolution to a gradual evolution, as Darwin had postulated. And furthermore, because this fitted with natural selection, they now accepted Darwinian selection which the Mendelians had not. And this was, in a way, a synthesis of… between Darwinian thinking and the new findings of genetics. However, this particular synthesis of 1916 to 1932 was totally different from the synthesis that began in 1937 which was initiated by the publication of [Theodosius] Dobzhansky's book Genetics and the Origin of Species, in which the synthesis was established between two major fields of evolutionary biology: the field that studies adaptation, which was done mostly by the geneticists, and the field characterised by species and speciation and macro-evolution which was the major interest of the naturalists. And it was Dobzhansky's book which helped to bring together these two fields and their representatives. And both… the representatives of both fields saw that they were right in some things and wrong in others, that they were very knowledgeable about certain things in evolution and quite ignorant about others and by putting the two fields together all the gaps could be filled and all the misunderstandings be eliminated. And that is what happened in that second… in that third period of these three periods, the one from 1937 to 1947, and that was the real so-called evolutionary synthesis that now everybody talks about.