Social environment and moral progress / by Alfred Russel Wallace.

  • Alfred Russel Wallace
Date:
1913
Catalogue details

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

Credit: Social environment and moral progress / by Alfred Russel Wallace. Source: Wellcome Collection.

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    Environment and Moral Progress [ch. of Acquired Characters. The effects of use and disuse, another form of the same general phenomenon, were assumed by Lamarck to be inherited, and a large por¬ tion of his theory of evolution rested on this assumption ; it seemed so probable, and was apparently supported by so many facts, that Darwin, like most other natural¬ ists at the time, accepted it without any special inquiry, and when he worked out his theory of Pangenesis in order to ex¬ plain the main facts of heredity, his sup¬ positions were adapted to include such phenomena. Let us then first explain what is meant by the acquired charac¬ ters which it was thought that a true theory of heredity must explain. As a rule, the great majority of the peculiarities of any species of animal or plant are constantly reproduced in its offspring. The short taü of the wren, the much longer tail of the long-tailed tit, the crest of the crested tit and of in¬ numerable other birds, always when full-grown exhibit the same characters as in their parents. These are said to be innate characters. In rare cases, how¬ ever, offspring are born which differ mate¬ rially from their parents, as when a white 104
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