How Birds Survive at Sea. The (incorrect) view from the 1930s in a popular article from a renowned ecologist

Occasionally I see a paper or article that I wish had had seen earlier. This is one of them.

Animal and Zoo Magazine, under its earliest title, Zoo, had the great advantage Julian Huxley as its advisory editor and backer with the Zoological Society of London. He could get former colleagues and students from Oxford—very often the leading zoologists of the 1930s—to write articles describing for the general public their research in a wider context.

The sixth issue of the magazine in November 1936 contained an article on seabirds. It is one I wish I had seen in the 1960s or early 70s since I would have quoted it in our book on salt glands for the then current view of how seabirds survive at sea, before, that is, Knut Schmidt-Nielsen discovered salt glands in the 1950s and really explained how they did it.

The title was ‘Wings Over the Sea’ and the author was Vero Copner Wynne-Edwards (1906-1997). He was then at McGill University in Canada, formerly at Oxford, the marine laboratory in Plymouth and Bristol University. He described very well what was then known of the natural history of seabirds. He included some of his own research on their distribution nearer or farther from land, which contributed to his election to the Royal Society in 1970, and stressed the differences between, say, gulls, which never move far from a source of freshwater to others from far out in the oceans which appeared to survive without freshwater. He explained the prevailing view: ‘As a group, birds are no more able to drink salt-water than mammals, and a diet of salt water instead of fresh is quickly fatal to those land birds with which experiment has been made’ and ‘In the ordinary combustion of food substances, the principal end-products are carbon dioxide and water; and it is possible that by exercising the most rigorous control of water excretion, other birds and mammals which live permanently out of reach of fresh water manage to make do with what they derive from this internal source. They may also, however, be able to manufacture fresh from salt water in their kidneys and cloaca’.

Later, after salt glands had been discovered, a general relationship emerged between the size of the salt glands and Wynne-Edwards’s ecological classification of seabirds and their habitat. Thus those that occur inshore have smaller salt glands than those that range to the edge of the continental shelf which in turn have smaller glands than the truly pelagic species, like albatrosses. What is important to remember is that all seabirds have salt glands that can be activated within minutes of having to ingest sea or estuarine water or invertebrate prey high in salt. Ecological questions though do remain. For example, removing excess salt via the salt glands is energetically expensive, and so what is the trade-off in inshore birds between flying back to land and a source of fresh water (which Wynne-Edwards described in gulls) or staying out at sea and letting the salt glands operate?

V.C. Wynne-Edwards
(from Newton - see below)

Wynne-Edwards who, in this popular article, was quoting the views of physiologists of the time was a renowned practitioner of the observational natural history approach to ecology rather than the experimental or quantitative. Nearly 25 years after writing this article he was Professor of Zoology at Aberdeen. There he wrote his book, Animal Dispersion in Relation to Social Behaviour, which was published in 1962, a book that contained a revolutionary idea in evolutionary biology that was to be shot down in flames and to remain shot down. Wynne-Edwards proposed the idea of ‘group selection’ from his work on birds—that animal populations collectively regulate their own numbers in order to prevent the overexploitation of their resources. The gatherings of birds from whole areas in communal gatherings he interpreted as means of assessing the size of the population by its members. A group breeding to excess and therefore profligate with its resources would be selected against while one that regulated its numbers would have, in the long-term, greater success.

The idea of natural selection operating on a group, rather than on an individual, was, of course, contrary to accepted Darwinian views and it was not long before the killer flaw in Wynne-Edwards’s hypothesis was spotted: a group of animals behaving in the restrained, conforming way that he proposed would be unable to resist invasion by a selfish genotype, i.e. one that did not conform. In short, the selfish would outbreed the selfless social conformer.

Despite being shot down, the book was very influential and more biologists than would later admit to were rather attracted to its tenets since the cosy social organisation it implied often matched the political world view of the readers as to how human beings should behave.

Wynne-Edwards stuck to his ideas throughout his life, in print that is. He was reluctant to discuss his views with others, even refusing to take questions at the end of an invited lecture or seminar. Sadly, his obituarists concluded, group selection had become an article of faith.

In the 1980s I met Wynne-Edwards in Aberdeen a couple of times. I was also struck by his aloof demeanour and unwillingness to engage on any topic, even after a glass or two. My impression was that he actually had rather a hard time as head of a university department and Regius Professor—and he was known to stand on ceremony—whose big idea had been so publicly and so effectively pooh-poohed. So I actually felt rather sorry for him. It seemed to me, from reading the hoo-ha over his book in the 1960s and later, that he had taken the interpretation of his observations too far and that instead of publishing his hypothesis in a fully-formed book he should have first explored his developing ideas more openly at conferences and with others interested in the overall problem.

But then, finally, I got another impression of Wynne-Edwards. My late assistant was visiting her mother-in-law in a care home in Banchory. There she had tea with her mother-in-law’s new-found friends—the Wynne-Edwards. She told me of this the next day and of how welcoming and friendly they were. In later visits (I had told her the history of group selection) he explained something of his earlier work on seabird distribution and on fisheries, the human management of which, of course, parallels his ideas on the natural control of populations.

Wynne-Edwards VC. 1936. Wings over the sea. Zoo [Magazine] 1 (6, November 1936), 18-21.

Paul Racey’s obituary for the Royal Society of Edinburgh can be found here.

Newton I. 1998. Vero Copner Wynne-Edwards, C.B.E. 4 July 1906–5 January 1997. Biographical Memoirs of Fellows of the Royal Society 44, 473-484.