“If two animals have a common ancestor, their parasites are likely to be descended from those of the ancestor.”

—  J. B. S. Haldane , book The Causes of Evolution

Introduction, p. 9.
The Causes of Evolution (1932)
Context: Comparative parasitology supports the evolutionary hypothesis. If two animals have a common ancestor, their parasites are likely to be descended from those of the ancestor. This principle has been applied with considerable effect to the classification of frogs and other groups.

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J. B. S. Haldane photo
J. B. S. Haldane 32
Geneticist and evolutionary biologist 1892–1964

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