Henry Walter Bates

Henry Walter Bates (1825–1892)

14,000 specimens

Henry Walter Bates, a trusted companion of Alfred Russel Wallace, travelled to Amazonia in 1848, where he became fascinated by close similarities in appearance between unrelated butterflies. Bates was to spend a total of 11 years in Amazonia, a vast network of largely unexplored major rivers and their tributaries set in the world’s largest area of tropical rain forest in South America. A great collector like Wallace, by the time he returned to England in November 1859 Bates had sent back over 14,000 specimens, mainly insects, over half of which were newly recorded species. 

After returning to England, he read Darwin’s Origin—and put forward his famous idea of mimicry as the explanation: poorly-defended butterflies could evolve to look like brightly-coloured, protected species avoided by predators. Starting with some initial, slightly deceptive resemblance, Bates argued this would be improved by natural selection to produce the remarkable similarities observed.

world’s largest area of tropical rain forest in South America

We are very lucky at the Society to be in possession of Bates’s original paper (Transactions of the Linnean Society vol. 23, 1862) in which he proposed his theory of mimicry. Shown here is a detail from plate 56 (Bates, 1862) showing two examples of mimicry discussed by Bates: Dismorphia (Pieridae) and Mechanitis (Nymphalidae) from Tefe (Figs 7, 7a), and Patia (Pieridae) and Methona (Nymphalidae) from Rio Cupari (Figs 8, 8a). The nymphalids are now known to be chemically protected.