Clashing views on how to recognise species in the 1950s. The case of the Treefrogs

By the middle of the 20th century the museum-based classical zoologists were being looked down on. Their traditional pursuit of describing, naming and cataloguing species that were believed to be newly discovered, or of revising classifications and taxonomy of whole groups of animals, was—and indeed in Britain still is—most definitely out of fashion. The classical museum zoologists, with some notable exceptions, had become wedded to the notion that only morphological characters could and should be used in systematics and taxonomy. What was once a necessary approach as the only one available had become a dogma.

Deryk Frazer, writing in 1983, provided a wonderful example in his recollections:

I remember a scientific meeting of the Zoological Society, where their secretary Lord Chaplin[*] gave a paper on the European and Mediterranean treefrogs (i.e. Hyla arborea†, meridionalis and savigny) where he covered their distribution and probable areas of origin, appearance—including differences in profile of nose and mouth which could only be seen in living individuals, and recordings of the mating calls. His conclusions were quite inescapable, that they were two distinct species, one of which was separated into two subspecies. One learned zoologist then rose to his feet and said that he was not prepared to accept this, because you could not distinguish dead individuals from one another. Nowadays we have the added weapons of sound spectrogram, chromosome picture and the results of hybridisation, for a start.

The attitude of the ‘learned zoologist’ with dead individuals I see being repeated by those of molecular persuasion, however incomplete, inappropriate or misleading their limited data on mitochondrial or nuclear DNA. Both the traditionalists and their modern counterparts remind me of the story of the drunk searching for his house keys under a street light. ‘Was that where you lost them?’ the passerby asked. ‘No, it’s the only place I can see’ was the reply.

This treefrog (Hyla arborea) we saw in Hungary in 2010
decided a shoulder was the ideal place to land

*Anthony Freskyn Charles Hamby Chaplin, 3rd Viscount Chaplin from 1949 (1906-1981) was Secretary of the Zoological Society of London from 1952 until 1955. An amateur zoologist and composer he had a miserable time as Secretary. He was in office when George Cansdale was sacked as superintendent of London Zoo. The presentation to the Society must be that given by Chaplin and Jack Lester on treefrogs and other amphibians which appeared in the account of meetings (Proceedings of the Zoological Society of London 124, 197-197, 1954).

†Recently ‘split’ into four species.

Frazer D. 1983. The British Herpetological Society—a reminiscence. British Herpetological Society Bulletin No 8 December 1983, 10-12.