Wednesday, July 8, 2020

Dick Jefferies (1932-2020) - a Personal Reminiscence

Dick Jefferies, and friend
Sad to say I have reached an age where my old friends, colleagues and mentors seem to be passing on. I had hardly come to terms with the loss of Jenny Clack -- if I ever shall -- when I received news, from his son Bill, that my old friend Dick Jefferies had died, on 23 June, after a long illness, aged 88. I wrote a public obituary, with Bill's help, and you can find it here. What follows is more of a personal reminiscence.

I first met Dr Richard Peter Spencer Jefferies, known to everyone as Dick, in the summer of 1983. I was lucky enough to have been awarded  a summer vacation studentship at the Natural History Museum in London, between my second and third years as an undergraduate at the University of Leeds.

My project involved working in the Fossil Fish section of the Department of Palaeontology. I didn't know it at the time, but the palaeontologists there were radicals, seeking to reform the world of the classification of life using a new method called 'phylogenetic systematics', or to its detractors, 'cladistics'. They included Colin Patterson (1933-1998); his former student Peter Forey (1945-2016), and their longtime associate Brian Gardiner (b. 1934), three of the four authors of a notorious paper that had been published two years earlier and which was seen as somewhat subversive. All I knew was that to most other scientists in the Museum, these people were Mad, Bad and Dangerous to Know. To an impressionable 21-year-old, they exerted a magnetic attraction (I wrote about this experience in my book Deep Time). They used to meet in a small coffee room-cum-library (that is, when they weren't at a pub called the Cranley in the Old Brompton Road, don't look for it, it's not there any more).

In the regular coffee-room crowd was a tweedy gentleman who didn't work on fish at all, but whose influence on the others was profound. This was Dick Jefferies, whose fluency in German allowed him to translate key texts on systematics into English. One was Die Ordnung des Lebendigen by Rupert Riedel (Order in living organisms: a systems analysis of evolution, John Wiley & Sons, 1978). He also attempted translations of some of Willi Hennig's work, but not (as I had previously thought) Phylogenetische Systematik: this was published in English as Phylogenetic Systematics, translated by Dwight Davis and Rainer Zangerl. These works were the foundation of cladistics. Over time, cladistics became the accepted way of doing things.

Geologist and polymath, fluent in six languages but absolutely English in every way, even down to his devotion to the Times crossword, I came to see Dick as the Last Victorian Scientist. He was one of those people who really did know everything.

Dick was born in Croydon, Surrey, on 15 January, 1932. Like many of his generation, he perhaps owed his subsequent career to the circumstances of war. He was evacuated to Steyning in Sussex, where rambles in the South Downs nurtured a love of natural history -- and, possibly, the chalk on which it rested. He was educated at Selhurst Grammar School and Gonville and Caius College Cambridge. There he became a geologist, specialising on the chalk over which he had roamed as a boy. His treatise on the Plenus Marls, a component of the Cretaceous chalk, became a standard work.

He met his first wife Beryl at a meeting of the Fabian Society, and, after a stint at British Iranian Petroleum he joined the staff of what was then (and to some of us always will be) the British Museum (Natural History). It was 1963. He was to stay there for the rest of his professional life.

The chalk contains many fossils of sea urchins, members of the group of animals called the echinoderms, and it was his interest in these animals that would shape his career. Besides sea urchins, echinoderms include possibly familiar creatures as sea stars, feather stars, brittle stars and sea cucumbers. All of them have distinctive skeletons made of calcite crystals, and a radial symmetry based on the number five. These are the ones alive today. Fifteen, maybe twenty other major kinds of echinoderms have evolved in the past, starting in the Cambrian Period (541-485 million years ago), and have since become extinct.

Although most had a five-way symmetry, some had a three-way symmetry, some were bilaterally symmetrical -- and a few had no symmetry at all. The lure of these very irregular creatures, the stylophora, or carpoids, drew Dick in. A favourite was Cothurnocystis elizae. Dick is holding a model of one of these in the picture above. The real fossils are very much smaller.

In fact, Dick's love of really strange fossils, as well as his towering erudition and total command of a voluminous literature in five languages besides English, made him the Museum's expert on 'Problematica'. That is, fossils so strange that nobody else could work out what they were.

The body of Cothurnocystis sports a series of openings on one side of its body. An earlier researcher had wondered whether these were gill slits, like those of fish (T. Gislén, 'Affinities between the Echinodermata, Enteropneusta and Chordonia', Zoologiska Bidrag från Uppsala 12, 199-304, 1930). Dick was transfixed. He took this idea much further, and in a long series of papers, from 1967 right up to his retirement in 1992, he argued, in immense detail, that Cothurnocystis and the other stylophora were not echinoderms at all, but chordates (the group of animals that includes ourselves). His idea, which came to be called the 'Calcichordate' hypothesis, was that chordates originated from echinoderm-like animals that had lost their distinctive calcite skeletons. Although it attracted virtually no adherents, critics were at a loss to know how to address it, so formidable were Dick's arguments, so immense his knowledge.

I returned to the Natural History Museum regularly, later in the 1980s, when I was working on my Ph.D. Although I had initially been signed up to do a Ph.D. on fossil fishes, in London, a series of unlikely events led me to a Ph.D. on fossil cows, in Cambridge. Being the good cladist that I was, I saw that fossil cows were just highly derived fish adapted for living in water of negative depth, sighed, and got on with it. Nevertheless I kept up contacts with my friends in the Fossil Fish section -- and also with Dick.

At Cambridge, I was enjoined -- as all graduate students are -- to teach small groups of undergraduates, and my task was to tutor them in the origins of vertebrates, a subject that had become of great interest to me, partly under Dick's influence. In those days (it was 1985 or so) very little was known, and the literature was scattered, antique and obscure. There being no consensus, I felt that Dick's ideas -- outré though they were -- were as good as anyone else's, and had the merit of being based on actual fossil evidence. Dick summarised his ideas, together with a truly masterly primer on vertebrate and echinoderm embryology and anatomy in a book in 1986.

I vowed to write a book on the subject that students could use. I embarked on it as soon as I had done with the fossil cows. After one paper on these, I set to work, with great enthusiasm, and the book came out in 1996. I devoted an entire chapter to Dick's work; not because I subscribed to it (I tried and tried, but could never really convince myself) but because I thought that in a field in which nobody really knew anything, all ideas deserved an airing, and Dick's was far better argued than most.

Colin Patterson wrote of Dick's ideas:
Jefferies’ work is original, gives careful attention to method, and has hardly yet been tested by criticism. Good tests will be molecular sequence data and parsimony analysis (e.g. of Jefferies' invocation of multiple loss of the calcite skeleton, and nonhomology of chordate and hemichordate right gill slits). If it passes these tests, the work may set a model for the future in its synthesis of neontology, paleontology, and method. ('page 216 in 'Significance of fossils in determining evolutionary relationships', Ann. Rev. Ecol. Syst. 12, 195-223, 1981)
Indeed, as Patterson had predicted, the calcichordate idea remained on the table until molecular biology caught up with anatomy,  showing that there was absolutely no trace in any vertebrate of the molecular genetic mechanisms required to create an echinoderm-like skeleton. Twenty years after my first essay on the topic, there is now a wealth of literature on vertebrate origins, which I reviewed in a book that appeared in 2018.

Dick was correct about three things, though: that many aspects of the internal structure of carpoids worked as he said they did, irrespective of their affinities, showing that they did have a very chordate-like internal anatomy; that sea-squirts are more closely related to vertebrates than the superficially more fish-like amphioxus; and that echinoderms really did have fish-like gill slits, but lost them early in their evolution. Indeed, genes for forming gill slits seem to be a unique feature in deuterostomes -- the group of animals that includes echinoderms, chordates and marine worms called enteropneusts.

Dick was a fixture at academic meetings on a wide variety of subjects for several decades, and would often ask incisive questions from the floor. He was always keen to learn new things. Once, while on my way to work at the Submerged Log Company, I bumped into him on the Underground - he was on his way, he said, to the Science Reference Library, to read up on developmental biology. 'It's a different language', he said. And this from an adept translator, who knew how to navigate the many subtleties of technical papers in German.

In later life Dick suffered from absent-mindedness, and it became clear that he was slowly going down with dementia. Dick's was among the finest minds it has been my privilege to have known, making dementia especially cruel.  However, his son Bill told me that even in his last days he had a quality of life -- reading about palaeontology, and listening to Beethoven.

After Beryl died in 1989, Dick married Audrey Millar, who died in 2018. His third son, Robert, died in a cycling accident in 2011. He is survived by his two other sons Thomas (b. 1963) and William (b. 1965); three grandchildren, Theo, Alex, Eve and Louise; and an academic legacy far more profound than he realised.

Written with invaluable help from Bill Jefferies. Revised 11 July 2020, with additional material and incorporating corrections from Dr David Williams, with thanks.

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