Cannibalism strikes us as revolting but also fascinating. One occasionally hears of people driven to eat human flesh by extreme circumstances, or of the bizarre cannibalistic habit of an insane serial killer. Our fascination with cannibalism assures the success of occasional films, such as The Silence Of The Lambs, that feature the practice.
Popular preoccupation with cannibalism also finds expression in humour, and most books of humorous quotations feature a section on the subject. "I came across a tribe of cannibals who'd been converted by Catholic missionaries," goes one. "Now on Friday they only eat fishermen."
One well-documented case of cannibalism forced by circumstance is that of the Donner party, a wagon train that left Illinois for California in 1846. Some of the party got snowbound in the Sierra Nevada. Forty-two starved to death; others survived by eating some of the deceased.
It is widely assumed that, apart from rare and extreme circumstances, cannibalism has disappeared and was never practised widely. The first assumption is undoubtedly true, but there is much evidence that the second is unsound.
The Western world has been observing other cultures since about 400 BC. Accounts of cannibalism were not uncommon over a wide range of territory, from South America to the Pacific islands to central Africa. Many historical accounts of cannibalism are now viewed with suspicion or dismissed as travellers' myths - primarily because professional anthropologists were not involved in these observations until the late 19th century, but also because of political correctness.
Some 20th-century anthropologists extended their conclusions about cannibalism into the distant past and over a wide geographical field. Others interpreted prehistoric archaeological findings in Europe and elsewhere as indications that cannibalism was widespread from about 300 million years ago until relatively recently.
The field was re-evaluated in the 1980s, and it was decided that much higher standards of evidence would be required before anthropologists could conclude that cannibalism was practised at any particular time and in any particular place.
When one mammal eats another, it leaves evidence, such as teeth marks, on the skeleton. It was therefore reasoned that if cannibalism was practised in human prehistory, the bodies would be butchered with the same tools used to butcher other animals. Also, the characteristic cuts and fractures evident on butchered animal bones would be seen on any human remains.
Convincing evidence has been found in prehistoric European sites. Hominid bones and bones from prehistoric game, such as bison and deer, were found at a site in northern Spain that was occupied by human ancestors (hominids) 800,000 years ago. The hominid bones show clear marks of butchery, matching those on the animal bones. The marks indicate the body was skinned and flesh removed with stone implements, and the skull and long bones were processed for the removal of nutritious brain and bone marrow.
There is clear evidence that cannibalism was practised among European Neanderthals, who lived 35,000 to 150,000 years ago.
Recent discoveries at much younger sites in Colorado, in the US, have also shed new light on the Native American Anasazi culture. Human remains found at a 12th-century site indicate cannibalism. The remains of seven people appear to have been dismembered and defleshed. Some of their bones were pounded; others, covered in flesh, were roasted or stewed. Anthropologists found traces of human myoglobin, a protein found in heart and muscle, on a ceramic pot. Ancient human excrement also tested positive for human myoglobin. It should be pointed out that most Anasazi graves contain intact skeletons.
Research since 1980 has established that cannibalism was widespread in our collective human past, but anthropologists still do not know why.
A summary of this field by T.D. White appeared in the August issue of Scientific American.
William Reville is a senior lecturer in biochemistry and director of microscopy at UCC.