The major tenets of the recent hypothesis of punctuated equilibrium are explicit in Darwin's writing. His notes from 1837–1838 contain references to stasis and rapid change. In the first edition of the Origin (1859), Darwin described the importance of isolation of local varieties in the process of speciation. His views on the tempo of speciation were influenced by Hugh Falconer and also, perhaps, by Edward Suess (1831–1914). It is paradoxical that, although both topics were recorded in his unpublished notes of (...) 1837–1838, the second was not explicitly and fully discussed until the fourth edition of the Origin (1866). While no wholly satisfactory explanation of this paradox suggests itself, it seems probable that Falconer's work on the persistence of fossil species of elephant helped Darwin to see the wider significance of the tempo of evolution for his general theory. (shrink)

The place of man in Darwin's development of a theory of transmutation has been obscured by his manner of disclosure. Comparing the 1837–1839 period to his entire career as a theorist suggests that it was Darwin's practice to present himself and his work only before the most select scientific audiences, and then in accordance with their expectations. The negative implications of this rule for his publication on man are clear enough: finding no general invitation in science to publish as a (...) theorist and no contemporary scientific audience for the sorts of inquiries he was making on man, he was silent, at least until such time as he could publish on the strength of reputation alone. Now, with the availability of manuscripts from the early period, what was once hidden stands revealed. It is clear from Darwin's notebooks that man played a dual role in the formation of his theory: as a zoological species to be incorporated into the theory and as the primary vehicle for the study of behavior. On the first score, integrating man into the theory provoked Darwin to break with the traditional view of man's place in nature and to reject a major element in the scientific notion of progressive development. On the second score, the study of behavior led Darwin outside natural history and thence, unexpectedly, to Malthus and natural selection.One is left with the certainty that the subject of man was a central element in Darwin's formulation of his species theory. To an extent, then, the public judgment of Darwin was right all along, for the public had always sensed that Darwin spoke to a larger audience than that formed around science. On the basis of new evidence, we can add that Darwin drew from that larger audience as well. There are of course ironies to this conclusion: that Darwin the professional drew so heavily from fields where he was the amateur, that as a transparent man his inner life should prove so at odds with the manner in which he presented himself, and that his arrival at a strong sense of himself—the revolutionary “I” of his notebooks—should occur just as he stepped beyond science to engage the general culture. But when one considers the inherent difficulties of Darwin's subject and the magnitude of his claims respecting man, these ironies are perhaps not surprising at all but those of a kind which might be anticipated. (shrink)

‘Hitherto want of accuracy and definiteness have often been brought as a charge against geology, and sometimes only with too much justice’, wrote Archibald Geikie in a review of Sir Roderick Murchison'sSiluria(1867). ‘We seem now to be entering, however, upon a new era, when there will be infused into geological methods and speculation, some of the precision of the exact sciences’. Geikie's judgement echoed an appeal made some thirty years earlier by William Hopkins (1793–1866) that the science of geology needed (...) to be ‘elevated’ from a level of ‘indeterminate generalities’ to a rank among the stricter physical sciences. This paper aims to analyse, in the context of broader trends favouring measurement and mathematics in British scientific practice, Hopkins' role in the promotion of dynamical geology as a major new complement to stratigraphical geology such that, for example, in the first edition of Geikie'sTextbook of Geology(1882) the dynamical and stratigraphical components each filled 376 pages. (shrink)