Renowned anthropologist Eric Wolf once described his discipline as "the most scientific of the humanities and the most humanistic of the sciences".
Perhaps he was attempting to capture the uniqueness of a subject that can talk to both academic camps but, by the time he died in 1999, his words articulated the growing split within the discipline.
Today, anthropology is at war with itself. The discipline has divided into two schools of thought - the social anthropologists and the evolutionary anthropologists. The schism between the two is simple but deeply ingrained. Academics in the subject clearly align themselves with one side or the other; once that choice is made it defines their career.
The division lies in the question of whether or not anthropology is a science, and if it accepts that Darwinian evolutionary theory guides research into human behaviour and the development of societies.
On one side are the evolutionary anthropologists. "(They believe) our behaviour is based on things that we did to find mates in our years of evolution," says Alex Bentley, a lecturer in anthropology at Durham University. "Then we have the social anthropologists. Some of them really strongly reject this kind of thinking. They consider it reductionist. They are focused on the specifics of culture."
Put crudely, social anthropologists describe and compare the development of human cultures and societies, while evolutionary anthropologists seek to explain it by reference to our biological evolution. The two sides of the one discipline are struggling to unite.
"They just do not see eye to eye. They don't see anything the same way," says Bentley. "It can be very difficult. In some departments they hardly speak. Professionally there is almost no overlap. One is more descriptive and the other is more analytical. It's a very clear dividing line in many departments. It often causes a lot of acrimony."
This division dates back to the 1970s, when eminent American anthropologist Napoleon Chagnon (now retired emeritus professor at the University of California, Santa Barbara) presented his work on the Yanomami tribes of Venezuela in the context of evolutionary biology.
At first, evolutionary anthropologists were considered the mavericks of the discipline and regarded with both amusement and disdain. But the popularity of the subdiscipline has grown over the decades, and universities now face a challenge in keeping their anthropology departments operating civilly. The divisions within the subject are even guiding the hiring process, with many recruiters ensuring a balance of interests when hiring new staff.
"(Departments) might say: 'We'll have a social anthropologist this time but next time we can have a biological anthropologist.' It's that much out in the open," continues Bentley. Even undergraduates are forced to select one route of study or another from the outset. The effect on the subject is obvious: "While the two sides aren't communicating (the discipline) is not working as efficiently as it could," Bentley concludes.
Although the debate may be hosted within academe, there is nothing considered about the war of words exchanged between the two camps. Today's anthropologists are certainly not afraid of a bit of mud-slinging.
"A lot of anthropologists are interpretivists; they are interpreting what they see. They're not working within the framework of the scientific method," says Ruth Mace, professor of evolutionary anthropology at University College London. "That's all well and good, but why should we be more interested in one person's interpretation over someone else's interpretation unless we have got some commonly accepted grounds for testing competing hypotheses?"
For Mace, the debate over whether to work within the "scientific method" is holding anthropology back. "If you're interested in making formal hypotheses about why people do what they do, we have to test those hypotheses," she says. "I'm a scientist - that's what I do. I think that evolutionary theory provides a very real framework for trying to understand that. If a discipline isn't saying anything that is of interest to any other discipline then that is a problem. The scientific method is a common currency across all scientific disciplines, most of the social sciences included. In that way, disciplines can speak to each other."
Mace believes that cultural anthropology is still very dominant, and that trying to work as an evolutionary anthropologist is difficult within a British university. "It's unfortunate that the discipline's divided," she says. "It's difficult to do science in a non-science department."
But Tim Ingold, chair of social anthropology at the University of Aberdeen, finds this view hard to accept. He says it is the biological anthropologists' refusal to compromise that is at the root of the split.
"They seem to be stuck on a very rigid form of argument, and it's one which they're not prepared to question. They already assume they have the correct answer. It's extremely frustrating. They're not prepared to accept any kind of criticism from people on the social side," Ingold says. "From where I sit, the biggest obstacle to satisfactory integration in this way is this dogmatic adherence to a fairly orthodox neo-Darwinian paradigm.
"I have always seen anthropology as something that bridges the divide between science and the humanities, but the terms on which most biological anthropologists insist that (the two sides) should be brought together are completely wrong and unhelpful."
Indeed, Ingold is concerned about the rise of evolutionary anthropology in US academe. "Everybody looking across the pond would say that the way in which things have gone there has been unhelpful to the discipline."
When Ingold established the department of anthropology, he recruited a team of social anthropologists. Despite this, he deliberately chose not to call it the "department of social anthropology" as he did not want to be divisive.
He says anthropology is now locked in a stalemate for which he blames the lack of movement on the part of the evolutionary anthropologists. "They're just not prepared to compromise," Ingold says. "I believe anthropology should be a science but there are many ways of doing science."
How can the discipline expect to unite if neither side is prepared to talk to the other and to compromise? Despite the clear division, many anthropologists remain hopeful. They believe a common ground can be found, and are working to bring both camps together.
Harvey Whitehouse, professor of anthropology at the University of Oxford, is one of them. He aims to show how the two sides of anthropology can work in tandem, and tells social anthropologists that they must accept that biological differences have an impact on the development of society if academic research in anthropology is to progress.
"Over the course of the 20th century, anthropology became 'mindblind', but more generally the discipline developed a kind of biological myopia. The future of anthropology lies in the development of much sharper vision in these areas," wrote Whitehouse in an insert for Joy Hendry's An Introduction to Cultural and Social Anthropology: Sharing Our Worlds. "Just as feminist scholarship has begun seriously to grapple with and contribute to the discoveries of evolutionary sciences and experimental psychology, so too must anthropology ... In my own area of specialist interest, the anthropology of religion, there can be little doubt that natural features of cognition contribute to the content and salience of beliefs in the afterlife."
In fact, the recent book Religion, Anthropology and Cognitive Science, co-authored by Whitehouse, shows just how easily ethnography, history and cognitive science can be integrated in an anthropological study of religion.
"Children, it now seems, cannot be raised to believe just anything; nor can adults be converted to any type of ideological system," Whitehouse wrote.
"Religions must exploit certain fundamental universal human intuitive biases and predilections if they are to get a foothold. The cognitivist project has certainly been valuable in explaining why many features of religious thinking and behaviour are much the same everywhere."
The Royal Anthropological Institute is at the vanguard of a new unity within the discipline. Hilary Callan, the institute's director, says the charity exists to represent the interests of all anthropologists. As such it has inevitably faced its critics.
"The discipline has suffered from the progressive divergence between the sub-disciplines. There has been a tendency for the biological end to be associated with the political right and the sociocultural with the political left. I would not support that polarisation. I think it's a false one," she explains.
"We are positioned as an institution that's representative of all of the subdisciplines. There have been debates about whether there has been over-representation of the interests of social anthropology at the expense of biological and evolutionary anthropology."
But Callan is optimistic, and such criticisms have not deterred the institute from its aim of getting biological and social anthropologists talking to each other. The institute is hosting lectures with a focus on all disciplines bringing the two forks together - psychology and behaviour; nature and culture; Darwinism and religion.
It is also publishing new texts looking at the oldest questions of anthropology, such as kinship, with the newest cross-disciplinary theories. Callan calls this progress the "green shoots of new growth".
"If there has been a problem it has been a problem of separateness, but that separateness has not been complete and without exception. The issue of reaching across boundaries is not just a question of bringing together biological and social anthropology," she says.
New research subjects, such as medical anthropology and the anthropology of tourism, are examples of this reaching out. At Durham University, Robert Barton, head of the anthropology department, has deliberately recruited a team of academics who will work to bring the two elements of the one discipline closer together. He cannot understand why the two subdisciplines have been kept separate for so long, and believes that the division has led anthropology to lose its way academically.
"There was a kind of confusion about what the aims (of anthropology) were," Barton says. "We're interested in the same kind of phenomena. Sometimes we're working in parallel but not really talking to one another about what methods of study we're using and how these might contribute to each other's interests."
Barton's employment strategy has been aimed at bringing in academics specifically interested in exploring the areas of interaction between social and biological anthropology, whether they are from a scientific or humanities background.
"What I am interested in doing here is bringing together those people who really do have something to say to each other," Barton explains. "There was a real barrier to that happening in terms of lack of understanding. In particular I think many social anthropologists misunderstood evolutionary biology. They caricatured it. One of my missions has been to break down those misperceptions that everything we're doing implies genetic determinism."
Barton's researchers are working on overlaps between the disciplines, and are focused on research that will reveal new truths about the human condition. An example of such work includes an analysis into whether the evolution of a pastoral way of life in certain parts of the world is linked to the biological capacity to digest milk. "That's the kind of process that people are interested in," he says.
Barton believes that his work to unite anthropologists also creates an opportunity to engage academics outside the discipline in a way that has been impossible until now because of persistent infighting.
"I'm very optimistic. We're going to see real collaboration going on across the social divide," he adds. "I'm totally convinced that it's essential they come together. I don't think there's any future for an anthropology that doesn't combine the different approaches and perspectives."
However, even here among those working to get the anthropology factions talking again, opinions are divided. At the Royal Anthropological Institute, Callan says that although evolutionary and social anthropologists can certainly work together profitably, they will never be united.
"What I think will happen, and what I hope will happen over the coming period, is that the specialisation and the proliferation of really excellent research within the subfields will continue," says Callan. "But there will be a growing core of common interest looking at the themes from different perspectives, and raising new questions and new kinds of answers to them.
"There will always be many anthropologies. The discipline won't speak with one voice or look in one direction."