Read Dry Storeroom No. 1 Online
Authors: Richard Fortey
Punch
’s view of the obsessive lepidopteran collector, 1985
But if the removal of orange juice from breakfast menus might have been a source of irritation in the households of the west, it would be as nothing compared with the consequences of removing cassava from the diet of developing countries. Cassava (
Manihot esculenta
) is one of the most efficient of all domesticated plants for manufacturing carbohydrates—which is a good working definition of a staple foodstuff. What the potato was once for the Irish, cassava is now for the tropical peasant. Originally a South American species, it is the most important food crop in sub-Saharan Africa. But the crop was viciously attacked by a mealy bug from its home territory called
Phenacoccus manihoti;
these plant bugs look like scabs of cotton wool at first sight, but underneath the fluff they suck out all the goodness from their hosts till the plants turn yellowish, then sicken and die. A tiny parasitic encyrtid wasp from Paraguay came to the rescue; it was named
Anagyrus lopezi.
Mealy bugs of the cassava-consuming species were its favourite food. It does not figure among the most heroic creatures on the zoological hit parade, but this little creature probably saved many thousands of lives. Its recognition was the product of expertise in taxonomy, extensive knowledge of “hairs on legs,” a skill that might be considered esoteric until it becomes vital.
I have speculated from time to time as to whether researchers come progressively to resemble the organisms upon which they research. There is a certain amount of evidence for my thesis, although I doubt whether it would survive rigorous statistical examination. For example, I have come to resemble a trilobite as I have got older, particularly as regards the middle lobe of my anatomy. A former Keeper of Zoology, Colin Curds, worked upon very small organisms that lived in sewage, and he did indeed resemble some kind of obscure micro-organism such as one might observe on a slide, being a little man with a pointy beard who darted around in a manner rather like
Paramecium.
Gordon Corbet, who worked on small mammals, was a Scotsman with a hesitant manner and a nervous way of speaking; for some reason he reminded me of a vole—the way these animals pause momentarily, whiskers twitching. But there were some particularly striking examples in the Entomology Department. W. N. P. Barbellion (diary entry, 20 April 1914) had noted such resemblances when he remarked: “an Entomologist is a large hairy man with eyebrows like antennae.” Ian Yarrow worked on bumblebees (particularly the genus
Bombus
), and he was a man with a very comfortably rounded middle. He had a fondness for furry jumpers, which gave him a thoracic look, and on one occasion I saw him wearing a woolly sweater with broad horizontal stripes. Furthermore, he used to hum to himself: once I followed him down the front steps of the Museum as he bounced from foot to foot going “bzz, bzz, bzz” quietly. At the risk of spoiling my thesis, however, I should add that he smoked a pipe, which is most unbee-like. Dick Vane-Wright had one of the longest possible Museum careers, and rose slowly through the ranks to become Keeper of Entomology at the end of the twentieth century. He works on butterflies, particularly showy tropical butterflies, and, when compared with most entomologists, has an appropriately flamboyant personality; he was briefly fond of outrageous waistcoats with paisley patterns. He was also very partial to attractive women and took a genuine delight in beauty, and I cannot help thinking of him flitting butterfly-like from flower to female flower. Somehow, even his propensity for playing the trumpet seems concordant with his being a lepidopterist: all those long tongues pushing out of the mouth. If reincarnation were a possibility I would imagine Dick Vane-Wright as a red admiral butterfly opening his splendid wings in the sunshine upon a
Buddleia
bush. On the other hand, Barry Bolton, the incomparable ant man, was always enormously and single-mindedly industrious, just like…well, I hardly need to labour the point. He could also release a blast of acid when the occasion demanded it. Several of the beetle men developed hard carapaces and tended to avoid the daylight. The colourful botanist Edmund Launert has been mentioned—and he has published a standard work on orchids—while the fern man Clive Jermy tended to shun the limelight, and worked away modestly hidden in the shady crannies of the Cryptogamic Herbarium. As for the former spider man, he had eight legs and spent all day on a web (all right, I made that one up). As final proof, I am told that recently I have become more of an old fossil than ever before. I rest my case.
Dick Vane-Wright dressed as his subject of study: the Lepidoptera
There are some corners of the Entomology Department where few people ever venture. The towers of the Museum are the farthest reaches of Gormenghast. Even to find one’s way to the towers is an exercise in map reading. The visitor has to go through one door after another apparently leading nowhere. Then there are thin flights of steep stairs that go upwards from floor to floor; I am reminded of a medieval keep, where one floor was for feasting and the next one for brewing up boiling oil. I discovered part of one tower that could be accessed only by a ladder stretched over a roof. Nowadays, the towers do not have permanent staff housed there—something to do with them lacking fire escapes and not complying with some detail of the Health and Safety at Work Act of 1974. Instead there are empty rooms, or ones holding stacks of neglected stuff. A hermit could hide here, undiscovered. From the top of the towers there is a wonderful view; London is laid out just “like a patient etherized upon a table,” new landmark towers reaching above the fine old heights of St. Paul’s Cathedral in the distance to the east. But then: in plastic bags laid out on a bench there are dead piglets being eaten by maggots. On a side bench there is a register labelled “Calliphorid culture book.” This is the room where experimental decomposition of flesh by blowflies is under way under the enthusiastic supervision of Amoret Whitaker. Piglets are rather more available for experiment than human corpses. When the maggots have done their work, the piglet is reduced to skin and bones. Amoret waved such a filleted animal at me; it looked like a grisly deflated copy of the original rendered in parchment. Another bag was full of pupae—the next stage in the life cycle of the flies, which mostly belong to the Family Calliphoridae. These experiments are in the service of forensic entomology, an area of science where the police and the Natural History Museum enjoy a brief liaison over a body. Like undertakers, forensic entomologists seem to be a habitually cheerful lot. Ken Smith, Amoret’s predecessor, was quite happy to be known as Lord of the Flies. He published the standard textbook on forensic entomology in 1986. At that time the scientists gave weekly lectures to one another as part of the activities of a Scientific Officers’ Association. Ken Smith’s talk featured projection slides of decaying bits of anatomy. More sensitive members of the audience soon started to look green and staggered towards the door. As the slides got more graphic, more people left. Only a few policemen were left at the end, taking notes.
The entomology of corpse decay has become quite a sophisticated science. The premise is quite simple, at least as far as determining the time of death is concerned. There is a succession of different insect species with different life cycles that strip down a body. When a body is discovered, it is possible to determine approximately how long it has been lying around by capturing the insects and/or their larvae, and counting and identifying them. By far the best indicators are the common or garden bluebottles and their relatives. They get in first, and their life cycles are short and known in detail. No sooner does a corpse get laid out in the woods than it exudes a delicious odour—at least to calliphorid flies like bluebottles. They swarm from afar. Eggs are laid, maggots hatch out, consume the flesh, then pupate for some days—and subsequently hatch out again all hungry and ready to mate. So by examining the moult stages of the larvae if they are still alive, or seeing whether there are empty pupal cases around the corpse, it should be possible to tell how long the body has been exposed to nature. In temperate climates the rate of the fly’s life cycle will vary according to the time of year—the warmer it is, the faster it goes. Then there are many other insects that take the process of decay further, and all of them have wonderfully suggestive names: the coffin fly (
Conicera tibialis
); the burying beetle (
Nicrophorus
species); the sexton beetle (
N. orbicollis
); and the larder beetle (
Dermestes
), “reported as reducing a human body to a skeleton in only 24 days.” This last is the beetle still employed at the Natural History Museum to clean flesh off the bones of specimens destined for the osteological collections. Beetle larvae can cope with the tougher bits that blowflies eschew, such as skin and ligaments and tendons. They will be the last ones to leave our bones alone when our time comes. Put a late fellow of infinite jest into a pit with
Dermestes
and in no time you have the skull of a Yorick. The tank in which this process is allowed to happen in the cause of science is known as a Dermestarium.
There are many additional insect species that will call in on a decomposing corpse for a little bit of protein on the side, so a forensic entomologist must know a lot about the Class Insecta in toto. Zakaria Erzincliogglu, known universally as “Dr. Zak,” former Director of the Forensic Science Research Centre at Durham University, has described with Sherlock Holmes–like precision in
Maggots, Murder and Men
the inferences involved in some of his cases. The discovery of an obscure species of winter gnat and the absence of bluebottles might go to prove that a murder happened in the cold part of the year. You can almost hear the pipe being tapped out against the fender. “Surely you are cognizant of the habits of the winter gnat, my dear Watson.” There are many subtle variations in the way entomological evidence can be used, given differences in site and time of year and the covering, or not, of bodies—and whether a particular species of beetle happened to be in the vicinity at the time a cadaver was deposited. A famous case brought to the Museum involved the examination of “sweepings” from a murder site. Apparently the suspect claimed that carpets had been removed due to an infestation of fleas (suspicious stains, naturally enough, providing the alternative explanation). Microscopic examination of dust from the site showed none of the evidence of larval or adult fleas that should have been present if the proffered explanation were true. Case closed. This is negative evidence, of course, but perhaps not dissimilar to Holmes’ famous case of the dog that failed to bark in the night.
One place where the forensic entomologist
can
get to work on human bodies is the Department of Anthropology at the University of Tennessee, Knoxville. This utterly respectable academic establishment has become the centre of a modern human bone collection. This may seem an odd thing to aspire to, but it is actually rather rare to have a collection of skeletons for which the name, history and biography are known. This growing collection will provide a statistical basis for future anatomical and pathological studies; I am told that 75 per cent of the bodies used are donated by the families of the departed. This also provides an opportunity for the forensic entomologists to study decomposition under observed conditions, for the meat must be removed from the cadavers before they are incorporated into the collection. The bodies are left out in the woods to let nature do the work: those in the trade refer to it as the “Body Farm.” I must say that you have to be a forensic entomologist to contemplate with dispassion the fly-blown corpses scattered around in a progressive array of decay. Most of us would probably prefer to study butterflies.