But over the past 17 years, Otzi the Iceman has been the subject of rigorous forensic analysis, each study shedding further light on early human existence.

Now, a Scottish scientist who has played an integral role in unravelling the mystery has suggested Otzi may have used a prehistoric precursor of the first aid kit, after traces of six types of moss – some with medicinal qualities – were found in his stomach.

Since two German hikers made their remarkable discovery near the Austro-Italian border in 1991, specialists from around the world have dwelled on Otzi's mummified remains.

Evolutionary biologists, pathologists, archaeobotanists radiologists and anthropologists: all have devised their own theories, and a consensus exists over much of Otzi's life.

It is agreed that he lived around 5,300 years ago, and carried a bow, a quiver of arrows, and a copper axe, none of which prevented his violent death, aged around 45.

Many of the hypotheses, however, have proved contradictory. As the tools with which scientists mine their information improve, new theories have been unearthed and older ones dismissed.

What is without doubt is the exhaustive nature of the work, perhaps best exemplified by the efforts of Professor James Dickson, a specialist in archaeobotany – the study of plant remains from archaeological sites.

He began the search to unravel the mysteries of Otzi's life 14 years ago. Now retired, Prof Dickson, 71, continues to break new ground, analysing fragments barely visible to the human eye that were found next to the iceman, on his clothes and in his gut.

Prof Dickson's research on what he calls "one of the greatest and least expected archaeological discoveries of all time" began in 1994, when he arrived for the first day of the summer term at the University of Glasgow.

He had previously enjoyed a good relationship with botanists in Innsbruck, and knew of the recent discovery of Otzi. As such, he had been tasked with an important research project. Waiting on his desk was a large box bearing an Austrian postmark; inside were 47 glass vials his friends in Innsbruck had asked him to examine.

Since that day, Prof Dickson has played a pivotal role in the study of Otzi and his life, scrutinising more than 100 minuscule pieces of moss, liverwort, and other fungi and macrofossils.

Numerous byzantine techniques have been involved, from stable isotope analysis to sequential sampling of food residues found in Otzi's digestive tract, painstakingly extracted in the specialist refrigerated cell at the South Tyrol Museum of Archaeology in Bolzano, northern Italy, where Otzi's body is stored at a constant temperature of -6C.

Commenting on his most recent discovery from Otzi's intestines, published in the journal, Vegetation History and Archaeobotany, Prof Dickson suggests one type of moss found, Sphagnum imbricatum, is a natural antiseptic and could have been used to heal wounds that were found on his back and hands. Another moss is believed to have been used to wrap his food and keep it fresh.

"If he knew of the useful properties of bog mosses, as seems plausible, then he may have gathered some to staunch the wound or wounds," Prof Dickson said.

It is just one of several key findings by various scientists that have taken years to uncover.

The seminal discovery that Otzi was killed in violent circumstances came only in 2001, when an Italian radiologist revealed X-rays showing the iceman had been shot in the back with an arrow.

Only this autumn, meanwhile, improved DNA analysis allowed researchers to announce that Otzi belonged to a previously unknown branch of the human family tree, a lineage that is either extremely rare or now extinct.

As far as Prof Dickson is concerned, Otzi's body may be guarding many more secrets, only some of which might be unearthed with further advances in technology.

Yet more than 5,000 years after Otzi walked the earth, the study of his ancient life goes on. "In principle, scientific work on the iceman can go on indefinitely because the corpse is very carefully kept frozen," Prof Dickson said.

"As more and more non-invasive techniques are discovered, so we shall learn about the life and times of this unique man."

BACKGROUND

SCIENCE has sought rational answers surrounding his life and death, but a terrible mythology has grown up around Otzi the Iceman.

Seven people involved with the corpse since its discovery in 1991 have died, either through accident or illness, leading to suggestions that there is a curse similar to that associated with Tutankhamun's tomb.

Helmut Simon, the German hiker who found Otzi, fell to his death in the Alps, and an hour after his funeral, Dieter Warnecke, the head of the mountain rescue team that found him, was struck down by a heart attack.