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Updated: May 3, 2025
Darwin "held that it was not the sudden variations due to altered external conditions which become permanent, but those slowly produced by what he termed 'the accumulative action of changed conditions of life." Nothing can be more soundly Lamarckian, and nothing should more conclusively show that, whatever else Mr.
The Lamarckian hypothesis has long since been justly condemned, and it is the established practice for every tyro to raise his heel against the carcass of the dead lion. But it is rarely either wise or instructive to treat even the errors of a really great man with mere ridicule, and in the present case the logical form of the doctrine stands on a very different footing from its substance.
In other countries it has a larger proportion of distinguished supporters. The general issue, however, must remain open. The Lamarckian and Weismannist theories are rival interpretations of past events, and we shall not find it necessary to press either. When the fish comes to live on land, for instance, it develops a bony limb out of its fin.
"Nevertheless," he says, "it is probable that the hearing rather early in life such views maintained and praised may have favoured my upholding them under a different form in my Origin of Species" a remark which refers to Lamarck's views on the general doctrine of evolution, but might also prove equally true if applied to Darwin's partial retention of the Lamarckian explanation of that evolution.
Yet the doctrine of Charles reached him, though the doctrine of Erasmus had passed over his head. Why did not Erasmus Darwin popularize the word Evolution as effectively as Charles? The reason was, I think, that Circumstantial Selection is easier to understand, more visible and concrete, than Lamarckian evolution.
The Lamarckian explanation of this fact would be that the earliest forms in the ancestry of the giraffe as such stretched their necks as they fed, and that this peculiar function with its correlated structural modification became habitual.
If he did, he saw no escape from the dilemma, for it seemed to him that the record in the rocks clearly disproved the alternative Lamarckian hypothesis. And almost with one accord the paleontologists of the time sustained the verdict. Owen, Agassiz, Falconer, Barrande, Pictet, Forbes, repudiated the idea as unqualifiedly as their great predecessor Cuvier had done in the earlier generation.
A frequent and a just objection to the Lamarckian hypothesis of the transmutation of species is based upon the absence of transitional forms between many species. But against the Darwinian hypothesis this argument has no force. Indeed, one of the most valuable and suggestive parts of Mr.
This last contrast goes deeper even than the one we have already noted, that between the Darwinian and the Lamarckian principle of explanation; and it leads ultimately from the special Darwinian problem to quite a new one, to be solved by itself—the problem of the nature and secret of living matter. Weismannism.
Since his death, moreover, his disciples have tended to split into two schools. On the one hand, Weismann has rejected the Lamarckian factors, the effect of use and disuse upon organs, and the transmissibility of acquired characters. The importance of these factors has been emphatically re-asserted, on the other hand, by Lankester and others.
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