The Natural History Museum in London might seem an unlikely participant in the frontline of the fight against grisly crime.

But then few museums can boast staff with the specialist skills of Amoret Whitaker, a motorbike-riding zoologist who is one of its two forensic entomologists - experts whose craft is focused on helping police in murder investigations, principally by examining maggots and other insect life found in and around a corpse to determine a time of death.

Whitaker is a prime example of a growing trend for the NHM and other British museums, responding to the dire squeeze on their finances from government spending cuts, to sell and market their expertise as consultants.

The NHM, which has a staff of some 300 scientists and researchers working behind its famous gothic facade in south Kensington, made £611,000 ($1,132,300) last year - an increase of 73 per cent over the past five years - from its consultancy services, which range from helping to catch murderers to pinpointing agricultural parasites to helping customs officers identify smuggled rare species.

Other world-famous institutions are increasingly jumping on the consultancy bandwagon.

But it is within the august walls of the NHM, a high temple to the Victorian ideals of public education and the showcasing of Britain's scholarly ambitions, that perhaps the most success in selling commercial services is being recorded.

The museum has contracts with the Metropolitan Police and two forensic science laboratories to provide its experts for crime fighting services, which also include forensic botany and forensic anthropology - the analysis of bone remains.

It is also taking a proactive approach to securing further contracts and tie-ups, taking an exhibition stand this month at a forensic sciences trade fair in London's Olympia.

The services of Whitaker and her colleagues are increasingly in demand. For more than a decade, she has picked her way around some of Britain's grimmest crime scenes, seeking to decipher nature's clues on issues from the drugs ingested by a person before he or she died to whether a carpet had been used to wrap a body.

She said: "The police wanted to know if a carpet which had been thrown out had had a big flea infestation, as was claimed by its owners, who kept dogs.

"I took a mini-vacuum cleaner to their home to discover whether there were large numbers of fleas. The indications were that there had not been a large infestation. After the police put this to the people concerned, it turned out that their son had killed a person and he was charged with murder."

It is just one example of dozens from more than 200 cases where Whitaker and her colleague, research entomologist Martin Hall, have helped cast light on the circumstances of high-profile killings.

As understanding of the evidential value of forensic entomology has spread among police forces, so demand for its services has accelerated. The museum has handled 48 cases in the past three years.

Maggots help provide clues

The central premise of the science is the fact that from the moment of death, a body starts to decompose and give off specific odours or chemical signals. For the Calliphora genus of blowflies - which includes the common or garden bluebottle and greenbottle - this perfume is irresistible. Once the flies reach a corpse they will immediately start laying eggs, beginning the stomach-turning lifecycle of larvae or maggots feeding on the remains, pupating and becoming adult flies - the root of the forensic entomologists' science.

By minutely observing and preserving the insect life on a body and in its immediate surroundings, the growth rates of the maggots and pupae can be compared with published data and live samples can be grown in the NHM's "insectary", where they are fed on dog food, to discover their age.

Given a whole range of variables, Amoret Whitaker can establish a minimum time that a person has been dead.

"The most important specimens are the larvae which might have already moved off the body because they have finished feeding," she said, "so that is why you have to look at the surrounding area."

The result is a complex but fascinating science.

- Independent