Transmutation of species

Transmutation of species or Transformism are terms often used to describe 19th-century evolutionary ideas for the altering of one species into another that preceded Charles Darwin's theory of natural selection. The French Transformisme was a term used by Jean Baptiste Lamarck in 1809 for his theory, and other 19th century proponents of pre-Darwinian evolutionary ideas included Étienne Geoffroy Saint-Hilaire, Robert Grant, and Robert Chambers who anonymously published the book Vestiges of the Natural History of Creation. Opposition in the scientific community to these early theories of evolution, led by influential scientists like the anatomists Georges Cuvier and Richard Owen and the geologist Charles Lyell, was intense. The debate over them was an important stage in the history of evolutionary thought and would influence the subsequent reaction to Darwin's theory.

Transmutation was one of the names commonly used for evolutionary ideas in the 19th century before Charles Darwin published On The Origin of Species (1859). Transmutation had previously been used as a term in alchemy to describe the transformation of base metals into gold. Other names for evolutionary ideas used in this period include the development hypothesis (one of the terms used by Darwin) and the theory of regular gradation, used by William Chilton in the periodical press such as The Oracle of Reason.Transformation is another word used quite as often as transmutation in this context. These early 19th century evolutionary ideas played an important role in the history of evolutionary thought.

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