David Hopkin Lewis, B.A., D.Phil. (1937–2023)

David Lewis (Figure 1), who died last year at the age of 85, regularly attended paper-reading meetings of the BBS, and its annual general meetings, from the 1960s to the 1980s. He was a frequent speaker on bryophyte biochemistry. His studies of soluble carbohydrates and lignin in bryophytes were groundbreaking, drawing on his considerable chemical and technical expertise, although he happily admitted his reliance on BBS members for the identification and collection of source materials.

Figure 1. David led celebrations of the centenary of the New Phytologist in 2002. Photograph: Peter Ayres.

David was born to Emlyn and Eluned Lewis, who ran a tobacconist shop in Glyncorrwg, South Wales. He developed an interest in plants from an early age. Aged 9, he was sent to the Colston School (now Collegiate School) in Bristol. School was followed by National Service in the RAF, with a period serving in Cyprus. This marked a final break with Wales, although throughout David’s life he remained staunchly proud of the nation and its rugby team.

He went up to the Queen’s College, Oxford, in 1957, achieving a first-class degree in botany in 1960. David took full advantage of all the university had to offer and developed that extremely broad view of botany which was to be the hallmark of his scientific career. In 1964, he completed a D.Phil. on the ectomycorrhizas of beech, under the supervision of Professor Jack Harley. Many years later, David remembered the day when he and Jack were shown Aneura mirabilis growing in birch woodland. They were struck by the remarkable parallel with the achlorophyllous orchid Neottia growing under beech: both the liverwort and the orchid obtain their carbon from adjacent trees via parasitism by their respective endophytic fungi.

Unlike most botanists of his generation, who took up lectureships immediately after completing a Ph.D., David enjoyed several years as a postdoctoral researcher. In collaboration with David Smith in Oxford, working on the physiology of symbiosis, he accumulated an extensive body of knowledge regarding carbohydrate metabolism and storage in relationships involving not just higher plants but also bryophytes, fungi and algae (both free-living and in lichens).

In 1966, David become a lecturer in botany at the University of Sheffield, where he remained for the rest of his career. His research flourished, as described below, and as a consequence of his all-round academic talents coupled with a naturally relaxed personal charm, David rose quickly through the university hierarchy. He was awarded a personal chair in 1983 and was appointed head of his department in 1987.

The 1980s was an unhappy period for the science of botany; it was too often perceived as quaint and old-fashioned, if not antediluvian; student numbers were falling in universities. Changes in higher education policy during the Thatcher years, 1979–1990, deemed small departments inefficient. And botany departments were typically small. The names of some departments were altered from ‘Botany’ to ‘Plant Sciences’, while others were subsumed into larger groupings. Today, fewer than a handful of free-standing Plant Sciences departments remain. At Sheffield in 1988, ‘Botany’ merged with ‘Zoology’ to become the ‘Department of Animal and Plant Sciences’, with David as its head. Whereas similar mergers elsewhere resulted in the almost complete disappearance of plant-based courses, botany thrived in Sheffield. Its respected position worldwide is today due in no small part to David’s supremely broad vision and managerial skills. From 1995 to 1999, he was Sheffield’s Pro Vice-Chancellor for Research. Although at first sight a highly prestigious position, it proved for David a poisoned chalice, because it involved implementing funding and staff cuts (and, as he wryly remembered, introducing highly unpopular car parking charges).

Outside his Sheffield University activities, David was from 1970 to 1983 an editor of the New Phytologist journal, subsequently serving as its Executive Editor from 1983 to 1995. Under his guidance, the journal was transformed from one whose subject matter was all too often of interest only to British readers to one of the most highly ranked broad-spectrum international botanical journals, particularly renowned for its wide-ranging subject matter, which included many important bryological papers. Critical to this transformation was David’s appointment of editors from around the world. Each was a leading figure in his or her own discipline; their names attracted important papers to the journal. Realising the potential of the not-for-profit (charitable) nature of the journal, in contrast with the model used by journals owned by commercial publishers, David ensured that income from the New Phytologist was used to organise international symposia on topics of widespread interest. David commissioned in-depth reviews from world authorities, inviting them to not just be objective but, in the spirit of stimulating discussion, to offer their own subjective opinions on their subject. Today, the New Phytologist is a model for scientific publishing.

For David, it was not just the measurable success of the journal that brought him pride but also the ‘family’ atmosphere he nurtured among editors and staff. Annual meetings of editors were part-social events to be enjoyed by all (including partners). Everyone felt they had a part to play and that their efforts contributed in some small way to the success of the journal. This spirit of inclusivity characterised his whole approach to science.

David’s D.Phil. research at Oxford had relied heavily on the use of paper chromatography, a cumbersome and exceedingly slow technique for identifying carbohydrates. The faster and more accurate methods of gas liquid chromatography (GLC) were becoming available by 1966, when David moved to Sheffield. At the University of Leeds, Patrick Holligan was perfecting methods of GLC for the analysis of carbohydrates. With advice from David, Holligan extracted and analysed carbohydrates from a range of photosynthetic organisms, including bryophytes, and from fungi. After completing his Ph.D., Holligan took his expertise to Sheffield, where he and David investigated carbohydrate transfer in rust-infected leaves and soluble-carbohydrate diversity across bryophytes. David believed (Lewis 1970; Suleiman et al. 1979) that a knowledge of these, and notably certain rare polyhydric alcohols, could be used to reorder the taxonomy of leafy liverworts. So it has proved to be. The untimely early death of his researcher, Alison Christie, curtailed his practical bryological work because, at heart, he was more a synthesiser than a benchworker. However, his interest in bryology was undimmed.

David welcomed and helped everyone who shared his interests. He liked nothing better than an integrating theory that challenged the botanical community; for example, he speculated that the absence of lignification in bryophytes is related to their polyol content, which effectively sequestered boron, that element having a key role in phenol metabolism and lignin biosynthesis (Lewis 1980). His work was certainly a catalyst for studies by others, although we now know that lignin does occur in bryophytes and that the claims for boron were unfounded. Despite being severely disabled by Parkinson’s disease in his later years, David was still able to engage in a lively debate on the role of boron in land-plant evolution (Lewis 2020).

David is survived by his wife, Diana (née Petrie), whom he married in 1990, and his children, Tom and Katie, from an earlier marriage to Rachel Waterfall.