While audiences may be thrilled by Hannibal Lecter�s exploits, we remain appalled by cannibalism. However, as archaeologist Timothy Taylor explains, the practice of eating our dead has a long and natural history �

FOR an intelligent thriller writer such as Thomas Harris, the name Hannibal must have been a no-brainer: a pregnant rhyme, and a hint at the megalomaniac ambition and failure of the Carthaginian general, ruthless even by local standards (ancient authors and archaeological skeletons tell us that children were publicly sacrificed in Carthage). Hannibal Rising tips us into the traumatic childhood of the central character of the Silence Of The Lambs series. As first the SS and then the Red Army overwhelm his native Lithuania, the young Hannibal Lecter sees his parents killed, and his beloved little sister cooked.

His genealogical descent from the ruthless mediaeval count, Hannibal the Grim, is counterpointed by a psychological descent, prompted by atrocity. Examining the birth of strange and criminal appetites, such as a taste for human flesh, Harris's prequel - first a book, now a film - neatly tracks a modern attempt to understand the excesses of adult psychopaths in terms of their personal histories, and of the deep, bestial past that we all share.

As an archaeologist specialising in the extremes of human behaviour, I know that, although Hannibal, son of Hamilcar was familiar with many types of killing, cannibalism was not one of his cultural habits. It could have been: across the Atlantic, the Aztecs liked eating people so much that they built it into the central rituals of their civilisation. Their high priests let the aromatic smoke from the choicest morsels drift up to the gods as a bribe for future well-being.

Today, faith in supernatural goodwill has been largely replaced by faith in medicine. While eating bits of each other is not looked on favourably, any one of us could be offered another person's heart for direct insertion by a trained surgeon. Transplants aren't cannibalism are they? Obviously, it depends on precisely what we mean. We care about identity, etiquette and value, in ways that run deeper even than religious sensitivity. If cannibalism today meant nothing, you would expect some atheist ecologists to plug the recycling angle; they don't. This is strange when we consider that cannibalism was present in a wide range of ancient cultures, and is basic primate behaviour.

Cannibalism is rife in nature. Once seen as an unremarkable part of scavenging and eating whatever was already dead, the "necrophagy" of seagulls, pigs, rats, hens and dogs was well known to naturalists and farmers long before the Victorian period. The indiscriminate hunger of creatures, such as salmon, that produced profligate numbers of unidentifiable offspring, seemed equally uninteresting. More careful and committed study of animal behaviour in the wild has shown that well over 70 species of mammal sometimes eat their own, and kill to do so.

If a male lion takes over a pride, why should he stop at killing his rival's cub when he could eat it as well? There are few social niceties in the wild, and the presence or absence of protein is, for most animals, the critical survival factor. Animal cannibals are not cutesy Disney characters gone bad, but simply the fat victors in a survival competition with a ruthless genetic logic.

So, when a formidable scholar and wildlife advocate such as Jane Goodall reports, regretfully, that wild chimps, male and female, singly and in groups, not only kill and eat young gibbons, but also baby chimpanzees, this tells us something about the underlying proclivities of our species as well. This is the evolutionary baggage we were carrying when we split from the rest of the apes. So did acquiring the intelligence to make chipped stone tools curb such appetites? Hardly.

Item: Sterkfontein, South Africa, two million years ago; Homo habilis cranium with cut marks made in the fresh bone where the lower jaw was removed. Item: Gran Dolina, Spain, 800,000 years ago; Homo antecessor remains, extensively butchered with stone knives. Item: Bodo, Ethiopia, 600,000 years ago; early archaic Homo sapiens cranium covered in cut marks from systematic defleshing. Item: Zhoukoudian, China, 400,000 years ago; Homo erectus crania with enlarged hole at base for extracting brains. Item: Moula Guercy, France, 100,000 years ago; Homo neanderthalensis, two juveniles, butchered just like the deer from the same site. Item: Gough's (New) Cave, England, 12,500 years ago; modern Homo sapiens remains, butchered in the same manner.

Some of these cut-marked bones could be interpreted as evidence of competition between different hominid species. For several million years, down to the extinction of the Neanderthals just before the peak of the last ice age, our line was one of several competing types of intelligent, upright-walking ape. But probably the distinction between any particular band of "us" and any group of "them" was made according to need. Allegiance to species and loyalty to tribe were interchangeable.

The 19th century ethnography of aggressive cannibalism hints at this: the hunted and eaten enemy was conceived of as bestially "other" - dog, pig, vermin. By contrast, eating some types of animal was taboo because they were thought of as clan members, more "human" than the enemy.

Enemies were denied access to one's own deceased relatives. Faced with the endless quest for enough food and the ever-present threat of attack, not only would I not mind if my grandchildren planned to eat me when I died, I would absolutely insist that they did. What better way to add a long-term survival advantage to my genes?

Edibility led to reverence. The first evidence of ritual funerary cannibalism dates to around 250,000 years ago, and continued in some remote areas into modern times. Among the Yanomamo of Amazonia, the thought of leaving a dead child in the forest alone, at night, to be crawled over by spiders and rooted out by scavengers, was a horror. Born of their parents' bodies, they came back home to the same inner warmth and protection in a funeral feast for which the word "cannibalistic" sounds somehow wrong. Yet even the bones were cooked, ground up, mixed with plantain and drunk. The Yanomamo rite left no archaeological trace, and that was the idea: nobody, human, animal or supernatural, could expropriate their dead loved ones. Ironically, in the face of missionary outrage and Western ways of thinking, the tracelessness of such acts has led to a revisionist history of denial.

Such denial was not possible in the case of the Fore of Papua New Guinea, whose funeral conventions were similar. In the 1950s, the tribe was decimated by a mystery disease, kuru, that caused staggering and a slow death through nervous malfunction. Finally identified as a "prion protein" illness, it was linked to the women's habit of snacking on the brains as they prepared cannibalistic funerals.

Scientists renewed their interest in kuru after the mad-cow scandal and the appearance of new-variant CJD in humans. Genetic evidence now suggests a significant level of resistance to prion protein diseases, not just among those Fore who survived their local epidemic, but globally. The simplest explanation is that our evolutionary ancestors frequently ate each other, and that periodic outbreaks of nasty, cannibalism-related illnesses, have left our species with a degree of immunity. Mad-cow disease in humans could even have arisen from "cannibalism at one remove": medics writing in The Lancet recently argued that infected human tissue from incompletely burned Hindu cremations may have found its way into blood and bone meal sold for cattle feed.

But our ancestors did slowly retreat from cannibalism. The reasons were not sentimental, but to do with conspicuous consumption. Not eating the dead is showing off: "Look: we've got this meat thing sorted!" Forest hunter-gatherers could not afford to do this, but the new farmers, who began to appear around 10,000 years ago, had regular meat supplies and could "waste" corpses in the ground. If they really wanted to rub it in, cremation was even less energy efficient, taking tonnes of timber and producing remains too charred to eat.

Cannibalism was on the ropes with the onset of farming, and the knock-out blow came at the last supper. In requesting a memorialisation of his flesh and blood in bread and wine, Jesus signalled an end to blood sacrifice. But if it had just been a religious ideology that missionaries brought to the last cannibals, they might still have persisted. Instead, by the end of the 19th century, a new level of consumerism consolidated the emerging taboo. Appropriately, in my old Encyclopaedia Britannica, the topic "cannibalism" is directly followed by "canning". With the rise of food processing at the end of the 19th century, any easy tolerance of survival cannibalism - whether on some backwoods expedition, like that of the infamous Colorado cannibal, Alferd Packer, or among desperadoes clinging to a raft in open ocean - evaporated. By the 1880s, eating people had become a mark of failure, and to succumb - under whatever duress - was not so much two fingers up at the priest as an affront to the supremacy of industrial food production.

Central to Lecter's grisly magnetism is his avowed gustatory pleasure in human flesh. Most real-life psycho cannibals have been pretty poor cooks, although Nikolai Dzurmongaliev seems to have been good enough to have served around 200 young women to a succession of unwitting guests (released from psychiatric care, he is reportedly living with relatives somewhere in eastern Europe).

Harris's monster is monstrous because he couples an admirably cultured life, of painting, music, science and medicine with an appetite conditioned by war yet rendered unnecessary by the post-war economics of plenty. His compulsion is not that of a ravening madman. He does not just eat the brains of the US Department of Justice agent, Paul Krendler, while the latter is still alive, but dines on them, with all the trappings of a gourmet.

Like Bluebeard before him, Lecter is a necessary creation. Where Charles Perrault's fairytale captured the essence and rumour of actual domestic serial murderers (such as the 15th-century wife killer, Cunmar the Accursed; the occultist child rapist, Gilles de Rais; or even our very own, legally above-board, Henry VIII), so Harris's Lecter stands in for Armin Meiwes, Ed Gein, Nikolai Dzurmongaliev, Albert Fish, Jeffrey Dahmer, Andrei Chikatilo, Issei Sagawa, Arthur Shawcross, and all the rest in the depressingly long catalogue of cannibal murderers convicted in modern times.

In Brazil, researching a television programme about "vampiric" psychopaths, I recently found myself standing outside a secure psychiatric institution in Niteroi on the outskirts of Rio, watching as staff, entered and exited the heavily guarded premises that currently house Marcelo de Andrade. Convicted of 14 grotesque child killings, involving rape and blood drinking, Andrade, dubbed the Vampire of Niteroi, has been presented in lurid true-crime anthologies as displaying a twisted compassion. By exclu- sively killing pre-pubescent boys, it is claimed that Andrade was ensuring that they were never able to know sin. We are asked to believe that he himself believed that he was dispensing eternal salvation, like a priest. And that, by drinking the blood of his victims, he sought also to ensure his own physical incorruptibility and immortality.

A child prostitute from the favela of Rocinha, Andrade grew up under the influence of a strident brand of evangelical Christianity. At the height of his murder spree, he visited the Universal Church of the Kingdom of God four times a week. This neopentecostal outfit goes large on demons, homophobia and the transcendent power of Jesus's blood. The church elders, reticent about its infamous connections, would not grant me an audience, so I visited the similarly influential Church of Jesus of the Last Days for a flavour of their usual proceedings. It was most educational. Having weathered nearly three hours of declamatory hellfire, I was "invited" for a personal exorcism by the pastor. While I remain sceptical that I have had a demon removed from my stomach, I was certainly left with a new sympathy for Marcelo in his confusion.

In the end I didn't meet him. His fellow inmates make his life in prison hard, and his psychiatrist, Claudio Bastos, decided that my visit would not be in his patient's best interest. He also thought that I would get little sense from Andrade, as he explained when we met. My session with Bastos was as rationally enlightening as that with the pastor had been mystifyingly intimidating. He told me that all the stories about Andrade's modus operandi were essentially just that, stories, borne of our understandable need to place the actions of an aberrant individual into some kind of framework of logical action.

"Insightful" Machiavellian psychopaths exist only in Hollywood, just because they would be a contradiction in terms. Andrade's actions were poorly planned, spontaneous, and driven more by a sadistic and erotic obsession with young boys than by theology, and no matter how many half-understood justifications he may have taken from the Universal Church of the Kingdom of God.

Much of prehistoric cannibalism was like this too. Not so much thought out as done, and justified, if necessary, after the event. People were always hungry, and they were aggressively competitive. Those dying knew that if they did not enjoin their relatives to take sustenance from them in death, the other tribe would take it for themselves. This was not a complex motivation, but a basic reflex. Only later, in times of greater plenty, did justifications develop and symbolism elaborate itself. We still seek to impose more meaning on the basic atavistic brutality of cannibalism than it will bear.

Hannibal is easier to read about than any real criminal. His urbane charm encourages us to stick with him and catch an oblique glimpse of horrors.

Andrade and the others, as they emerge from their potted biographies, have implausibly neat motivations. Since their actual brain processes are too scarily disordered for any but specialists to calmly grasp, we try to understand their actions as if they involved warped yet genuinely human decision-making. Lecter helps us to do this. And, if he is an implausible psychopath, he is a very plausible throwback. What really shocks us about him is his recognisable civility - a man conscientious enough to care about something. Not just meat, but cuisine with a long history.

Dr Timothy Taylor is an archaeologist at the University of Bradford, author of The Buried Soul, and a presenter of Discovery Channel's Real Vampires, due to be screened this autumn.

Hannibal Rising is released on February 9