Plants colour our world. How and why they do this are questions that have brought out the extremes of human behaviour, from the highest scientific achievements to the depths of human irrationality. It's a stirring tale. Are you sitting comfortably? Then we'll begin…
As a general reader and at first glance, you might be forgiven for thinking that you need a degree in plant biochemistry, or at least aspire to one, in order to understand The Tale of the Three Little Pigments, and there is no doubt that this is an excellent up to date guide for students of the plant sciences. For anyone unfamiliar with the basics of plant biology, this is perhaps one of the more challenging of professor Howard Thomas's books to date, but he does present his material in such a way as to reduce the complexity as much as possible without overly simplifying the content. As the author stresses, he is more concerned for the reader to grasp the outline rather than focus on the detailed chemical structures and nomenclature. For the more curious, each section is followed by detailed footnotes and there is a combined index and glossary of those acronyms not made explicit in the main text.
As in his previous books, each page can be read as a stand-alone bite sized chunk of information and the science is always related to the practical import of what follows from it. Opposite each page is a pertinent illustration or photograph. Insights and discoveries related to the topic in hand are often placed in a historical context in terms of how researchers, many of whom are now recognised as very eminent scientists, have contributed to our understanding in this area.
The first section provides a good lead in to the subject with an excellent summary of the physics of light and colour. The following sections deal in some detail with the major plant pigments, including porphyrins such as the chlorophylls, that largely reflect green light in land plants; terpenes such as the carotenoids, that largely reflect orange and yellow light; and flavonoids such as anthocyanins which largely reflect red, blue and purple light. As 'sedentary beasts', plants have had to develop different strategies compared to animals in order to use resources and gain protection. A whole range of key molecules, such as those just outlined, along with some fascinating and complex biochemistry are involved in these processes. At first sight, plant pigments might seem of either esoteric or of minor interest, but as the author explains the science underlying their purpose and production, it reveals quite a lot about how and why plants work as they do.
Thomas is particularly good at placing science in a social milieu and uses well-chosen examples. He also doesn't shy away from discussing controversial issues, e.g Golden Rice. In general he takes a fairly neutral approach to the issue of biotechnology and crop improvement, implying rather, that it behoves us all to understand a least a little of what plant scientists have done and can do, if as consumers or producers we want to make informed and sensible decisions about such matters.
Born and educated in Wales, after a career in scientific research, Howard Thomas is now emeritus Professor of Biology at Aberystwyth University. This allows him to carry on as he says 'with all the nice parts of the old job (writing, research, hanging round with other scientists, journal business, drinking too much coffee), much to the envy of my hard-working friends and colleagues who have to do all this as well as admin, politics and fund-raising. It means that I’ve been able to indulge a long-standing special interest in the science-humanities connection. I’ve also led a parallel life as a devout jazz musician.'