Dry Storeroom No. 1 (47 page)

A devotion to bold theories is not confined to distant days. A year or two before I joined the staff of the Natural History Museum Dick Jefferies published the first of his many scientific papers on some odd, ancient fossils called carpoids that are found in rocks of Cambrian to Devonian age, that is, from about 520 to 364 million years ago. I have discovered new species of these peculiar animals in Ordovician strata, and there is no mistaking them when the rock is split open to reveal one lying inside because many of them are curiously irregular looking—Dick always compared these animals to the shape of a boot. They had a covering of calcite plates, like many marine animals, but the plates have a particular structure which is typical of the Phylum Echinodermata—“spiny-skinned” animals: sea urchins, starfish and their allies. So for many years they were assigned to that group of animals without much comment, although it was acknowledged that they were oddballs in the phylum. Dick Jefferies had other ideas. He believed he recognized features on these strange creatures that were fundamentally similar to those on primitive chordates—the group of animals that includes vertebrates like fishes, frogs and ourselves. Over many years he described minutely and named many of his animals, and fitted them into the basal “twigs” of a tree of relationships that included major groups of chordates. Dick’s opinions were expressed in a deep voice, punctuated occasionally by a hearty guffaw; he is one of those people who dig deeply into anything that captures their attention—so he knows all about linguistics, and Chaucer, and is fluent in German, which he learned because he needed to read classical German works on embryology. For a while his theories were taken seriously by many of those interested in the deep branches of the history of life. Dick’s basso profundo could be guaranteed to ring out across the conference floor if any topic touching on vertebrate ancestry was raised. At the same time molecular evidence confirmed an old idea that vertebrates and echinoderms had descended from a common ancestor perhaps a billion years ago. Dick’s ideas were taken up by one of the editors of
Nature,
Henry Gee, who wrote a book,
Before the Backbone,
giving the carpoid hypothesis favourable coverage. Research students came to work in the Natural History Museum on new discoveries of the strange fossils, including some I had found in the Ordovician rocks of Shropshire in the company of my friend from the National Museum of Wales, Bob Owens.

However, throughout the 1990s, support for the Jefferies theory was slowly ebbing away. Several of Dick’s students came around once more to the idea that carpoids were a specialized group of echinoderms, more closely related to one another than to the several basal branches of the chordate tree.
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They were an interesting side-branch of evolution rather than a seminal one. Some of the evolutionary transformations that the Jefferies theory required began to seem overly complicated. As it got more elaborate, the theory began to buckle under its own weight. When more examples of new species were collected, even the geological record of the fossils seemed to be distinctly out of phase with the supposed relationships on the Jefferies tree of descent. Dick did not take kindly to being deserted by his ex-students. He would mumble darkly about being “stabbed in the back.” It was distressing to see the pain this caused to such an admirable and profound scholar. As with so many people in this book, he has continued to work on undaunted after official retirement, still convinced that the world will come around to his view. I hope that the world does just that, but it is progressively unlikely. However, regardless of the grand evolutionary design, all future students of the carpoids will have available Dick Jefferies’ names, and meticulous descriptions of these long-extinct organisms. This work will last, even as theory moves on, as theory should. I do not suppose that this will cheer up the good Dr. Jefferies, true though it is. He has a slightly wistful air these days.

The carpoid
Cothurnocystis elizae
Bather, Ordovician, Scotland. These odd animals have been the centre of a long debate about the origin of vertebrates.

I have explained in the previous chapter how the capacity to secure external funding is now regarded as a sine qua non as a measure of success for scientists. Now we come to a crucial paradox. It is very hard to get grants to study organisms and update their taxonomy. From the accounts of current research I have given in this book it will be clear just how varied is the research agenda across the Museum. Some kinds of research—such as that on schistosomiasis, or on insects that damage crops—are obviously commercial. Other fields of investigation, such as that on marine nematodes, might sound arcane at first, but can soon be rallied to the cause of monitoring environmental pollution and the like. It might be hard work to get external funding to study nematodes and greenfly, but it can be done. Mineralogy and mammon have performed a pas de deux ever since the days of Georgius Agricola. The history of mankind always has a certain cachet, and anthropologists come in with a head start in the Palaeontology Department, followed closely by dinosaur experts. Scientists with less obviously appealing areas of expertise begin to have a hard time.

Complaints about failure to receive funding can begin to sound like whingeing, and the list of unsuccessful applicants soon gets to be a long one. A short account of one of my own disappointments might stand in for many others. The definitive summary of fossil biodiversity is a series of books published by the University of Kansas called
The Treatise on Invertebrate Paleontology
—we usually just call it
The Treatise,
in the same way we might talk about the Bible. Most palaeontologists would not argue with the proposition that it is the most generally useful reference in the whole subject. Volumes treat taxonomic groups, such as trilobites or brachiopods, genus by genus, family by family. The original Trilobita volume was published in 1959, since when we have learned much, much more about these fascinating fossils. A revision was planned in several volumes. The first of these finally appeared in 1997, edited by my old Professor, Harry Whittington of the University of Cambridge; it covered only a small fraction of the trilobites. I was then asked to edit the subsequent volumes. With my other commitments it was clear I needed help, which meant giving employment to a bright young post-doctoral assistant. A grant proposal was prepared to this end with
Treatise
completion as the goal and sent to the UK’s Natural Environment Research Council. It got the bum’s rush; worse, it did not even pass through the first sift by the college of assessors to receive the scrutiny of an independent referee. Presumably, lack of hypotheses being tested was lethal; it was, after all, just a piece of stamp collecting. As a result I have been obliged to resign as editor: goodbye
Treatise.
Researchers more adept than I have managed to obtain funding for “classical” systematics by hitching up with molecular sequencers. For example, they might examine how systematics prosecuted using classical morphological characters match up with phylogenies derived from molecular evidence. We have already seen how Sandy Knapp got support for a definitive study—including molecular work—for the tomatoes and their allies. Recall David Reid and his winkles, or Paul Kenrick and his primitive plants. Many more proposals meet the same fate as did mine—consigned to the funding wastebasket. I know of people who reckon to spend almost half their time trying to raise money, time that might be better spent furthering their knowledge of animals and plants for the benefit of everybody. It is recognized that there has to be some form of selection, but classical systematic work is selected out too early.

However, given skilful legerdemain a systematic study can be wrapped in the finery of hypothesis testing, and the best young systematic biologists have become expert in a kind of creative duplicity. I suppose that I must be identified with those old sepia-coloured scientists with leather elbow patches if I protest that none of this tomfoolery should be necessary; that making known the biological riches of the world both past and present should not require subterfuge. I assert that taxonomy has never been more important now that so many of the world’s precious habitats are under threat. Knowing about biodiversity and taking steps to preserve it is no mere luxury—it may prove to be the criterion by which we are judged by our descendants. The pragmatic assertion that we might lose species of service to mankind—as a future source of drugs, say—may be broadly correct, but is not a morally compelling argument for conservation. Suppose, for example, that it could be proved that a rather rare species had nothing of worth for us humans locked away in its genome—would any decent person then set about exterminating it as a worthless organism? I doubt it. A better appeal for the pragmatist might be that we cannot know the consequences of damaging ecosystems that have taken hundreds of millions of years to develop. The precautionary principle is generally a wise one—but it is probably already too late for delicate habitats, especially in the oceans. In any case, the contention that we should know our fellow inhabitants of the home planet seems to me beyond argument. Biologists have done their best to unify respect for biodiversity by initiating such projects as the Tree of Life, wherein hundreds of individual scientists are collaborating to stitch together a map of relationships for all the organisms on Earth. The project reminds me of a collaborative patchwork quilt that was pieced together by a number of West Coast feminist artists in the late 1990s, in that the individual pieces have merit, but the completed whole will be more than the sum of the parts, and will make a political and moral point. On a practical level, some individuals contributing to the Tree of Life dealing with one or another group of organisms are obtaining funding for their work. The memorable label helps.

The basic kind of description and naming that Museum employees have carried out for so long is often called alpha taxonomy, beta taxonomy being systematic analysis and construction of evolutionary “trees.” This fundamental if superficially unglamorous science is the most difficult of all to fund, and, as the entomologist Henry Disney said in 2000, continues in “relentless decline” despite lip-service being paid to the importance of taxonomy following the 1992 Earth Summit in Rio de Janeiro. A positive result from Rio was the Darwin Initiative whereby Third World taxonomists could receive training from “western” experts; unfortunately, this did not guarantee the replacement of these experts in their turn. Henry Disney himself is an interesting example of achieving much on a shoestring. He has never received a research grant from one of the Research Councils, but in spite of that he has published from his Cambridge base some three hundred papers on scuttle flies (Phoridae), a group as diverse as they are little studied. During the 1990s he made himself unpopular in establishment circles by lobbying successive governments for information about what they were doing for taxonomy beyond rhetoric—and concluding that it wasn’t much. Since then a few hopeful signs have appeared. An American initiative opened up the possibility of funding for taxonomy from the National Science Foundation, the biggest teat from which scientists suckle on the west side of the Atlantic. The relevant acronym is PEET—Partnerships for Enhancing Expertise on Taxonomy—and the result has been that fresh-faced acolytes have been sitting at the feet of grizzled old experts and absorbing their lifetime’s experience.

Notwithstanding this hopeful harbinger, the progress towards an inventory of life’s richness still seemed too slow. By 2005 it had been estimated that some 1.7 million species had been described—far less than half the total on even the most conservative view. If taxonomists continued to name something like ten thousand new species a year, it would take several centuries to complete the task, and who could tell what might become extinct in the interim? And the latter category might include the taxonomists, too. When you learn that Henry Disney has named about three hundred species of flies it sounds rather a lot, but it is nothing compared with the task ahead for the scuttle flies alone. And most biologists would not want to stop with the name—they would want to go on to the interesting stuff about lifestyles and biology. One particular little fly studied by Henry lives by stealing pollen from the stores of bees—it just requires David Attenborough’s photographer to spend a month or two staking out the diminutive creature and you just
know
that fascinating film footage would follow. This is where nature gets really interesting—the name is but a necessary start. But there’s no time to linger on just one species—too much to do!

This is where the DNA Barcode comes to the rescue, at least in theory. The laborious business of characterizing a species can be speeded up immensely by using evidence from the genome: effectively DNA “fingerprinting” the species by using a sequence from a diagnostic gene. Formal names are not necessary. Now that determining sequences is fully automated, the whole process of identification can be done with the flick of a phial and the click of a switch. Farewell dusty old Sepia Man with his microscope and library; welcome Barcode Man with his primers and his white coat. Furthermore, since sequences can readily be posted on the internet, the diagnostic sequence can be instantly available around the world. The Genbank site is already an incomparable resource for those many scientists interested in the gene sequences of organisms and what they can tell us about evolution. When a gene is sequenced it is posted on Genbank—it has become a necessary part of the publication process at the time of writing. There are various computer programs which can match a sequence under study to those posted on Genbank, rather like a computer-dating system that looks for a close (though rarely perfect) match. The resource is utilized continuously for everything from researching the latest mutations of viruses to studying the evolution of earthworms. The Natural History Museum aims to “barcode” the British fauna and flora as part of this international endeavour.