Whatever you think of deer hunting, suggests Helene Guldberg, we should be far more worried by the 'scientific' assumptions supporting the National Trust's ban

Do deer suffer like us?

Over the Easter holidays my two-year-old nephew, much to everybody's amusement, panicked when he accidentally stood on a grape and cried 'Oh no, the grape's dead. I squashed it!'. His response of sheer horror was a healthy one considering his perception of the situation and belief that the grape was alive. If he had rejoiced at his accomplishment, or gone on to 'kill' more grapes, maybe even slowly peeling their skin off to prolong their ending, I would have worried about his state of mind.

Empathising with a grape is understandable, I suppose, in a two-year old. Many adults also have a tendency to empathise with all kinds of organisms - cats, dogs, even plants. We think our cat 'understands' us, our dog 'pines' for us, our plant 'needs some love and attention'. Although I must admit that I am no animal lover, I cannot see any harm in people treating their pet dog as 'one of the family' or even imagining that their pets share human emotions and human experiences. But I do see a problem with trying to rationalise such an outlook - trying to use it to understand animal behaviour, or taking it as a guide to public policy. Unfortunately, this is exactly what has happened with Professor Bateson's study for the National Trust.

The report, the outcome of a two year study, claims to show that deer hunted by hounds suffer extreme physical stress. The day after it was published, the National Trust, one of Britain's biggest landowners, moved to ban deer hunting on its land - despite a policy which held that it is up to parliament, and not the Trust, to make decisions on such matters. The people of Exmoor and the Quantocks, whose lives and livelihoods will be dramatically affected by the ban, were not consulted on the policy shift.

The National Trust argue that their decision was dictated by the science of the report. And Bateson argues that he went into the study with an open mind and a willingness to go wherever the science took him. That the human interests involved have been so casually brushed aside would have been bad enough if these claims were true. But the fact is that the science concerned does not back up the anti-hunting argument. Rather, a selective, at times wholly wrong, science has been used to legitimise anti-hunting sentiments.

What does the report tell us? The methodology Professor Bateson has used aims to provide objective criteria for measuring stress in animals. Not the kind of stress humans experience of course - such as worrying about losing your job or about the state of a relationship - but physical distress. Direct observations of the hunts and supplementary video footage provided data for analysing the deers' behaviour. Physiological profiles of culled deer are also presented, based on comparing blood samples taken from deer killed in hunts, stalked deer, deer injured in accidents and farmed deer.

As an ethological study, the National Trust report is interesting. The behavioural and physiological profiles provide some insights into how red deer respond in particular circumstances. The results show that deer pursued by hounds over long distances are driven to complete exhaustion. The measurements of blood carbohydrates show that in short chases lactate levels surge. But after about five kilometres the levels begin to fall - not because animal stress levels are subsiding, but because the animals are burning lactate as a means of fuelling their muscles. The carbohydrate resources for muscles are found to be totally depleted in deer chased for 30 kilometres or more. Hunted deer are shown to undergo levels of physiological change similar to that which happens to deer which were injured so severely that they were destroyed for humane reasons. The data on hunted deer contrasts strongly with data on farmed deer and clean-shot deer. Levels of cortisol are 10 times higher in deer chased by hounds than in those shot by stalkers. Levels of the hormone B-endorphin, associated with pain-killing, are also much higher.

Darwinian evolutionary theory can help us to understand the affect of chases. Red deer evolved in wooded areas where attacks by predators were likely to be sudden and short lived. They are not well-adapted to prolonged pursuit. They are not equipped with sweat glands in their bodies which means that they overheat when chased for longer distances, and their muscle fibre type is not suited for endurance running. Chased deer are, if you like, being forced to operate outside their 'design criteria'.

Bateson summarises this science - and draws the conclusion that the observed changes in physiology are indicative of stress and pain in the animal. He asks: 'Does the culling method cause deer to experience conditions lying far outside normal limits for the species?', and 'Does the culling method cause suffering (including anxiety, pain and injury) in red deer?', and answers yes to both questions.

He is undoubtedly right on the first point, about the abnormal conditions encountered by hunted deer. But he is just as clearly wrong on the second issue of suffering. The fundamental mistake is uncritically to apply human categories to animals. Bateson explicitly uses human categories to understand deer:

'Anxiety, distress, suffering and pain, as used in our study and in animal welfare legislation, are all defined in terms of human subjective experience. Such projection from human experience and emotions can be made transparent by building a profile of both the behavioural characteristics and the physiological processes involved when a human is in the specified state. This profile is used, with appropriate safeguards, when examining the character-istics of an animal exposed to similar stresses.'

The comparison is invalid precisely because animals lack 'human subjective experience' and 'human experience and emotions'. Undoubtedly, some animals are more complex than others, but none remotely approaches human mental states. As American biological anthropologist Kathleen R Gibson states: 'Other animals possess elements that are common to human behaviours, but none reaches the human level of accomplishment in any domain - vocal, gestural, imitative, technical or social. Nor do other species combine social, technical and linguistic behaviours into a rich, interactive and self-propelling cognitive complex.' (Tools, Language and Cognition in Human Evolution, 1993, pp7-8)

We can be sure that animals do not have the complex mental states of which Gibson writes because there is no behavioural manifestation of them. If animals had anything remotely resembling human subjective experiences they would exhibit the kind of intelligent behaviour, including the capacity for foresight and planning, that humans do. If deer, for example, had such mental states you would have expected them to have organised a little resistance to the hunts, or at least devised a means of escape, rather than waiting for the National Trust to move into action.

In the absence of such mental capacities we cannot specify any distinct 'experience' at all in animals. As the philosopher and Darwinian theorist Daniel Dennett explains, experiences must be the experience of a conscious subject, which understands what is happening to it, otherwise they are not experiences at all. And in the absence of distinct experiences, states such as physical distress do not have any clear significance: 'For such states to matter - whether or not we call them pains, or conscious states, or experiences - there must be an enduring subject to whom they matter because they are a source of suffering....Every experience must be the experience of some subject.' (Kinds of Minds, 1996, p163).

What Dennett is getting at is this: a deer, like any other animal, has no sense of itself. It has no idea what is happening to it at any one time, and is unable to reflect on what is happening by comparing it to what happened in the past. A deer does not say to itself: 'oh no, I'm being chased by those people that got my mate last week', which is just the kind of reflection on a chase that would really cause stress and anxiety. Humans have experiences; things just happen to animals. So wheareas it may be true that when animals, and humans for that matter, are forced to operate outside their 'design criteria' this has a detrimental effect on their biological well-being - manifested in physiological changes in blood pressure, stress hormone levels and the strength of the immune system - this alone cannot be referred to as suffering. Suffering, distress, pain and anxiety cannot be explained simply by physical changes. Rather, they are uniquely human experiences which arise out of the inter-action of such noxious stimulation and our ability consciously to experience it, to dread the consequences, and perhaps to fear repetition or even possible death to come.

Of course, the physiological basis of pain in humans can be explained in evolutionary terms just as the physiological basis of physical stress in animals can. But as intentional beings we make sense of and give meaning to physical processes, giving them a qualitatively different character from similar physical processes in animals. Humans are able to reflect on what they are doing and feeling. We contemplate our past and deliberate on what we might become. The behavioural aspect of what is so easily, but wrongly, called 'fear', 'pain' or 'suffering' in animals is in fact a simple adaptive response that can be explained through evolutionary theory and conditioning. There is no consciousness shaping the animals' reactions. Accordingly, we cannot talk about anxiety because there is no anticipation. Nor can we talk about pain because there is no self-awareness. Animals have no concept of death nor an ability to 'imagine the worst', which means there can be no sense of foreboding, dread, fear or anxiety.

The temptation to project human states onto animals is easy to understand: animals do appear to be 'suffering' and in 'pain' when they are subject to noxious stimulation. But two leading experts on pain theory warn us against even the idea that the animal is any way 'distressed' under the influence of such noxious stimulation. They point out that all the behavioural features we associate with pain or distress can show themselves even after the destruction of the cerebral cortex:

'Increased blood pressure, movements of withdrawal, dilatation of the pupil, increased depth of ventilation, attacking the source of noxious stimulation, and cries may be common to all mammals in the face of seemingly "painful" stimulation, but all such responses can be elicited after the cerebral cortex has been destroyed, in the probable absence of any subjective experience.' (A Jones and S Derbyshire, 'Cerebral mechanisms operating in the presence and absence of inflammatory pain', Annals of the Rheumatic Diseases, 1996, 55: 411-420)

In other words, even with the parts of the brain removed that are key to the processing of noxious stimulation, animals can exhibit the behavioural responses that would superficially indicate suffering or pain. So, it must be wrong to imply that patterns of animal behaviour are accompanied by internal mental states such as pain and suffering.

Accordingly, Jones and Derbyshire warn us against anthropomorphism: 'human interpretation of what is observed in another species cannot be by extrapolation from human experience.'

As Professor Bateson made clear he is aware of the scientific literature that stresses the unique character of human pain experiences. But for the purposes of the report 'I didn't think it appropriate to go into the subtleties of this debate'. This must cast doubt on Bateson's claim to have let the science lead him where it would, rather than allowing any preconceived notions about the ethical rights and wrongs of hunting to guide the study. Even if Bateson is merely presenting the science he believes to be correct, the effect of not discussing critical material is certainly to give the report the character of a propaganda tract for the anti-hunting lobby.

This is bad enough. But it is the broader implications of his approach that worry me most. Bateson's bottom-line argument is that 'animals have to be given the benefit of the doubt'. This has worrying implications for the integrity of scientific enquiry. To give animals the 'benefit of the doubt' amounts to saying that a scientific investigation of pain is of little consequence - since anything which counts against the idea of animal suffering can be ignored. Bateson is not merely refusing to engage with certain scientific ideas he finds uncomfortable; he is saying that a clash of scientific ideas is not the way to investigate the issue.

Giving animals 'the benefit of the doubt' also has implications for how we see ourselves. The richness of human experience, all the psychological states that give real meaning to pain and suffering, are trivialised because human experiences are lowered to, are equated with, those of animals. That science is now being mobilised not only to undermine hunting, but to belittle human experience should be of concern to everybody, not just those with a stake in chasing deer across moors.