The red notebook of Charles Darwin / edited, with an introduction and notes by Sandra Herbert.

  • Charles Darwin
Date:
1980
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: The red notebook of Charles Darwin / edited, with an introduction and notes by Sandra Herbert. Source: Wellcome Collection.

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    8 SANDRA HERBERT species (p. 127). Other statements challenge by way of example the notion that climate entirely determines the distribution of species (pp. 128, 134e) or that species are perfectly adapted to a particular set of physical circumstances (pp. 129, 133). Behind such statements lie broad questions concerning the relation of the history of the earth to the history of life. Yet in these passages the tentative and empirical nature of Darwin's inquiries is paramount. The second topic of interest with respect to the species question in the Red Notebook is the analogy Darwin drew between the distribution of species over space and over time. Darwin's statement reads: The same kind of relation that common ostrich bears to (Petisse, & diff kinds of Fourmillier); extinct Guanaco to recent: in former case position, in latter time, (or changes consequent on lapse) being the relation.—(p. 130) If we can simplify this statement by omitting the phrase 'diif kinds of Fourmillier' (on this see footnote 154 to the text), we have the following proportion: the common rhea stands to the lesser rhea as the 'extinct Guanaco' stands to the present-day guanaco. (The common rhea is Rhea americana, the lesser rhea the Rhea darwinii \Pterocnemiapennatd\. [See note 149 to the text.] The extinct Guanaco is Macrauchenia patachonica, the animal identified by Richard Owen; the present-day guanaco is Lama guanicoë. [See note 152 to the text.]) The first ratio, between the rheas, was based on spatial succession, the geographical ranges of the two birds being contiguous. The second ratio, between the Macrauchenia and the guanaco, involved temporal succession, although the exact nature of the succession is not speci¬ fied in the text. The common element binding the two ratios derives from the fact that both involved the replacement of one species by an allied species. Moreover, in context it is clear that replacement implied transmutation, for immediately upon asserting an analogy between spatial and temporal succession, Darwin referred to species changing. In doing so Darwin returned to a point we have noted earlier, namely his belief that allied species do not grade into each other. The Macrauchenia (or its cousin) must have 'inosculated' into the present-day guanaco, just as one rhea 'inosculated' into the other. For Darwin this ruled out the Lamarckian notion that one species gradually changed into another in response to 'degenerating circum¬ stances' as might be caused, for example, by a gradual change in climate. However, even if Darwin did not embrace a Lamarckian mechanism for species change, he did share Lamarck's conclusion that present-day species were descended from earlier related forms. A third topic taken up in the Red Notebook with general relevance for the species question was generation, or, in modern terms, reproduction. In the notebook Darwin dealt briefly with the particular issue of how he might regard individuation as occurring in the zoophytes, a now-abandoned grouping of plant-like animals whose most familiar representatives are the corals. (Red Notebook, p. 130) The technical nature of zoophyte generation was not Darwin's primary concern. He was chiefly concerned to see where zoophyte generation might fit in the general analogy he was drawing between the generation of species and the generation of individuals. The chief