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Spot the endangered species...

四月 22, 2005

...here's a hint: it has just two legs and is often found looking down a microscope at a specimen. Geoff Watts investigates the catastrophic population crash of the British beetle taxonomist

There's a whiff of naphtha in the air as Max Barclay unlocks a steel filing cupboard deep inside London's Natural History Museum. The curator of Coleoptera -beetles - scans down the flat cardboard boxes, each the size of a packet of soap powder, that are stacked on the shelves. He opens one. Arranged in rows and pinned into the base of the box are small pieces of white card. Stuck to each is a beetle - a total of some 150 in the first box we examine. There are 54 such boxes, the fruit of a three-week expedition to Borneo. Barclay reckons there are up to 8,000 beetles here and some will be new to science. In due course, they'll be sorted into families. Some will then be studied in-house if there's a suitable specialist on the staff. Otherwise, they will be sent to experts around the world who will examine them, keep duplicate specimens for their own collections and return the rest, both the identified and newly named, to London. Here the material will be added to the main beetle collection, which already includes specimens of no fewer than 200,000 species.

The logistics of insect taxon-omy on this scale are impressive; the Natural History Museum has long been a world leader in the field. It adds up to a remarkable repository of biological data with a host of uses, not least enabling conservationists to work out what species are out there and hence how they are faring. But there is a problem - British beetle taxonomists such as Barclay have long been in the grips of their own catastrophic population crash.

Colin Johnson recalls that when he was Manchester Museum's keeper of entomology he had an assistant keeper and a technician to look after 2.7 million insect specimens. Today, there is just a technician and no specialist in entomology, let alone beetles.

"In the 1800s and the first 30 or 40 years of the 20th century, Britain had one of the biggest entomological communities in the world," he says. "But in the late Fifties and Sixties this began to tail off. It seems that the generation working at that time didn't leave a successor."

His words are echoed by Henry Disney, sometime director of the field study centre at Malham Tarn in Yorkshire and now an honorary (in other words, unpaid) senior research associate in the Cambridge zoology department. "In this country, the majority of taxonomists are amateurs or retired professionals. There are some very good ones. Their great asset is their enthusiasm. But most British amateur entomologists are interested only in particular groups of native insects." And hence the already gaping holes in our collective knowledge are growing.

In fact, according to another former professional entomologist who did not want to be identified, there may be just five British alpha taxonomists, the elite who identify and describe new species, specialising in beetles.

Of them, one lives abroad, another is an ex-teacher in his seventies, two are retired museum staff and just one is in full-time employment in an institution. "This is a pretty poor show for a country that once dominated insect taxonomy," he reflects ruefully.

But even if it is true that 80 per cent of all species on the planet have yet to be identified, does it really make sense to collect and document every last living thing? While the conservationists naturally say yes, Disney offers a more practical argument. "Let's take an economically important group, the termites. Today there's not a single specialist in post anywhere on the termites of Africa. Jean Ruelle in Belgium is a specialist - but he's getting on and has cataracts." And it is not just termites, Disney adds. "Over the years I've been sent a number of pest species that have proved to be new to science. One I described was living on oyster mushrooms in India and later turned up in Korea, China, Switzerland and Poland. When a pest species is carried around the world before it has been described by science, this emphasises the parlous state of taxonomy."

Johnson attributes the decline to the rise of museum managers who lack a research background. "Also, when I was young, there were a lot of entomologists in the Manchester University biology departments. But in the Eighties and Nineties many of them retired and were not replaced."

Although not a uniquely British problem, Barclay thinks the decline has been particularly severe in this country. "Germany, Russia, Poland, America and the Czech Republic went on producing entomologists. So now much of our material has to be identified by specialists abroad."

Taxonomy is out of fashion in the UK. Barclay pulls open a few drawers at random. Many specimens are still housed in their original Victorian mahogany display cases. The workmanship is splendid - beyond the museum's current budget -but emblematic of the age of descriptive biology.

The rise of molecular biology may have played a role in hastening the field's demise but Barclay wonders if the end of the Empire might have played a part. "The taxonomists of old were much concerned with documenting the Empire," he says. "They wrote books with titles such as The Fauna of British India . Then we had the emergence of this new cutting-edge science that is independent of imperialism. University departments transferred their loyalty."

Disney also observes that taxonomy is undervalued in the research assessment exercise. And the criteria for getting a research council grant are often inappropriate. Applicants seeking support to write a new monograph on a beetle family may be asked to outline the hypothesis they're testing. But hypotheses are thrown up only when the work has begun to show anomalies in existing classification.

Meanwhile, as local authority museums cope with their own budget problems, the anonymous taxonomist notes that they have also been prioritising matters such as social inclusion, lifelong learning and events for families and children. "There's usually no extra money for this, so the collections suffer," he says. He was made redundant by a county museum and he says he felt almost relieved to abandon a job he no longer enjoyed. "I wasn't handling museum objects. I was doing health and safety, maintenance and forward planning."

In this climate, it is proving near impossible for a new generation of beetle taxonomists to establish a career. Disney points out that while the peak of creativity in, say, theoretical physics generally occurs early, the reverse is true in taxonomy. "To become a world expert you have to build up expertise over many years," he says.

The skills of the taxonomist are often as arcane as they are intricate.

Johnson is a leading specialist in the Ptiliidae or feather-wing beetles that are typically no more than half a millimetre long and are identified by dissecting their genitalia under a microscope.

More modern techniques such as DNA sequencing have revolutionised beta taxonomy, working out the classification of organisms according to their evolutionary relationships. But to know what each species is you need someone to analyse and record their morphology.

Despite a burdensome workload, Barclay is more optimistic than Disney or Johnson. He says that the Natural History Museum runs an MSc in taxonomic methods and that public and professional interest in biodiversity is helping to keep the need to catalogue all living things on the agenda.

And he smiles when he considers any suggestion that a high-tech approach might replace more tradition skills. DNA analysis illuminates phylogenetic relationships,he acknowledges. "But then you get a chap doing a PhD on the molecular phylogeny of weevils who comes to me and says: 'Excuse , but which of these creatures are weevils'."

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