Letters: December 2018

Progress problem

The science which won this year’s Nobel prize in chemistry, as described by Emma Stoye, (Chemistry World, November 2018, p20) is brilliant and fascinating. However it is a pity that the graphic chosen as the lead illustration, and reproduced as the cover picture of the edition, is the misleading cliché of a stepwise progression from chimpanzee to chemist. In many essentially similar forms, the ‘march of progress’ – as the picture is usually called – is surely the most widely recognised popular icon of evolution. As Stephen Jay Gould pointed out in his 1989 book Wonderful Life, this is regrettable for two reasons. One is that we are not descended for chimpanzees – we and they are cousins, descendants of a common ancestor. Second, the picture reinforces the notion that we are evolution’s greatest achievement – or even (perish the thought) that evolution had some kind of ‘aim’, and that was us. That’s not what Darwin meant at all.

Norman Kean FRSC
County Cork, Ireland 

Editor: the illustration was solely to communicate the idea of evolution, and is not meant to be taken as a suggestion humans are descended from chimpanzees or are the apex of natural selection.

What the Dickinsonia?

The November issue contained an article suggesting Dickinsonia have been confirmed as the first animals (Chemistry World, November 2018, p34). This summarised an analysis in Science concerning the classification of these species in the phylogenetic tree. The authors used as proof their identification of the typical animal sterol – cholesterol containing 27 carbon atoms – rather than the 28- and 29-carbon ergosteroids and stigmasteroids more typical of the non-animal kingdoms. However, it has been known for a long time that cholesterol and closely related 27-carbon sterols are the major sterols of several species of the plant Phylum Rhodophyta, containing mainly marine red algae. As far as I am aware, these are the only species of the plant kingdom which contain mainly cholesteroids. No one would be prepared to reclassify these species as belonging to the animal kingdom. 

Geoff Gibbons CChem FRSC
Oxford UK

Aryliodonium ylides

In connection with the article on radioisotopes in the October issue (Chemistry World, October 2018, p22), I feel that some additional information will clarify an obscure picture. It concerns the remarkable transformation of a ‘hypervalent iodinium ylide’, actually iodonium, generalised as ArI=C< , which is converted into ArF* by reacting with radiofluoride. Here, the leaving group is a bulky IC₁₃H₈O₄ spiro compound resulting from adamantanone and malonic acid. The full paper¹ constitutes a rare example of combining theoretical, mechanistic, synthetic and medicinal chemistry, and describes several potential radio-labelled pharmaceuticals of fairly complex structure.

Anastassios Varvoglis MRSC
Aristotle University of Thessaloniki, Greece 

Reference

B H Rotstein et al, Chem. Sci. 2016, 7, 4407 (DOI: 10.1039/c6sc00197a)

Summary solution

Stuart Goldie indicated the problems a PhD student has with the scientific literature (Chemistry World, October 2018, p5). The basic problem he identifies is there are too many papers and the quality is too varied. The other way of looking at the issue is this: we don’t know what we know.

The answer, for me, is curation. Within a very narrow field, the older experts more or less know the sum total of knowledge. My rule of thumb when entering a new field (and I have done this more than once) is that it takes at least five years to become reasonably familiar with the background information. That is not practical to ask of a PhD student. I think one aspect of the problem is that in science promotion, prizes and recognition tend to arise through the number of papers and citations you generate and, to some extent, who knows you. This imposes a strange orthodoxy: reviews get written, but the reviewers tend to be more concerned with including all relevant authors and noting their results so as not to impede that person’s career. Nowhere is there a return to the scientist on analysis of results.

When I started my PhD, a lot of work had been put into understanding mechanisms of a few important reactions, which led to the ability to know when to use them. Now there is such a bewildering number of papers that although a huge number of different reactions are known, it is not at all easy to find the key facts that must be known to predict whether something will work. We need more focus on summarising and condensing what we observe so the information is more useful and more generally available.

Ian Miller FRSC
Lower Hutt, New Zealand