Human Senses

The two senses we mostly rely on are vision and hearing. Normally, hearing is the first to be engaged when both audible and visual information is present - it's an attention attracter, which is why we find audible fire alarms work and why our phones and computers bleep.

This makes evolutionary sense, as sounds are not blocked by objects we can't see past, so they're useful as a danger signal that's likely to get through. But visual information is normally more engrossing and can convey more information. How much this is culture-dependent is an open question, but I suspect the auditory perception of typical urban dwellers is much less well developed than their visual, so there are probably latent capacities that could be re-energised.

We also unconsciously make use of other senses: touch - and not just via the hands - and smell contribute to our appreciation of our surroundings, but make a less significant contribution in an urban environment, so it pays to cultivate them for excursions into the wild.

Vision

Human vision is very good at detecting movement, particularly at the outer edges of the visual field. It's also good at recognising familiar shapes and regular patterns, but it doesn't resolve detail as well as that of some animals - particularly some predators. The limit of human optical resolution is often quoted as an inch at 100 yards (10 cm at 370 metres) or about 1 minute of arc, but most of us resolve less well than that, particularly as we get older. We don't see well in low light levels either, whereas many animals from cats to owls are specialised for night vision.

The one thing in our favour is a very sophisticated thinking brain that can extract a much wider variety of meaning from what we see than most other animals probably can. That of course is what seeing really is - extracting meaning from the signals arriving at the brain from our optic nerves. The actual image on the retina is not at all informative if we look at it directly, nor are the electrical signals at the other end of the optic nerve. It's our mental capacity that makes sophisticated seeing a reality. Indeed reports of people who've had their sight restored surgically after many years of blindness indicate that the greatest challenge they face is making sense of what they see. So to use our visual capacity to the full we have to cultivate meaning. For the wild soundscape recordist that means familiarising oneself with the visual detail of the specific environment - not only the shapes, textures and contrasts and the nature of their movements - both regular and exceptional - but how these fit together as a complete ensemble. Repeated observation using unfocused attention accomplishes this well, but concentrating on individual details tends to prevent the necessary holistic recognition taking place.

Hearing

Mechanically, human hearing is extremely sensitive - the ear can respond to an air movement as small as an atomic diameter. Indeed if it was any more sensitive, we would constantly be disturbed by the "noise" of Brownian motion - the random movement of molecules in the fluid of the inner ear. So at best our hearing is as sensitive within its frequency range as that of other animals. But they have an edge. We are normally much less attentive than they are because we have learned to ignore most of what is going on round us. Because we are almost constantly bombarded with loud and often meaningless sounds, we tend not to exercise the finer ranges of our physical capacity for hearing.

So for most of us, hearing is an under-used faculty. But there's much more to hearing than the simple mechanics of the ear. The most important part of hearing is interpretation, and that happens not in the ear or even the primary auditory cortex where the nerves from the ears enter the brain, but in the neocortex - the part of the brain we use for thinking and remembering. With the exception of sudden loud noises that may elicit the primitive fear response regardless of their specific nature, we tend to ignore sounds to which we can ascribe no meaning, or which from experience are irrelevant to us. As prior experience is the main source of the meanings and significances we attribute to what we hear, if we lack experience of a given environment and its characteristic sounds we may make little sense of the sounds around us or misattribute them to incorrect causes.

The optimum way to gain holistic understanding of the soundscape in an unfamiliar recording location is therefore not to concentrate on its most obtrusive elements or on individual details with the aim of trying to "identify" them, but initially to exercise broad unfocused attention and absorb the totality of the whole sound complex without exercising judgement or trying to label its components. The aim is to arrive at recognition of how the various independent sounds fit together as an ensemble. Only once that recognition has been accomplished will the individual components of the ensemble begin to make real sense.

Smell

The sense of smell is much less well developed in humans than in many other animals, but the modern urban-dweller's sense of smell is degraded almost to the point of extinction. Most of us are obliged to spend our lives in a miasma of transport fumes, in addition to which we voluntarily introduce dozens of synthetic "fragrances" into our environment. The powerful pong of "air fresheners" drowns other smells in our rooms. "Deodorants" replace natural body smells with unnatural ones derived from crude oil. Laundry detergents impart "spring-fresh" fragrances to our clothes and bed linen. Everyone's breath is supposed to be permanently minty. The problem of all this for the wild soundscape recordist - indeed for any naturalist or nature lover - is that we become walking chemical factories surrounded by an aura of smells that can be detected as exotic by wild creatures for miles around. So although we may not rely on our sense of smell directly in the course of wild soundscape recording, it's important to cultivate it in order to ensure we don't stick out like a sore thumb in the field.

Touch

A refined sense of touch via the soles of the feet is essential if we intend to walk quietly on the varied surfaces of the wild. Not only does that mean wearing suitable footwear - it also takes a lot of practice for urban dwellers used to stomping along on concrete paving. With the exception of a few environments such as rocks and screes where natural hazards demand strong boots, the lightest possible shoes should be worn. The Native American moccasin, with its hide sole a mere few millimetres thick, sufficed the wearers for hunting and tracking through forests and across plains. The primary benefit of such footwear is quietness of movement - primarily achieved by constant adaptation of the tread to the changing conditions underfoot. Sensing the nature of the ground via the soles of the feet, native hunters avoided the need to stare constantly at the trail immediately in front of them, and were thus able to direct their attention to their surroundings as a whole. A well-made heel-less boat shoe is a good substitute for the moccasin, but to take advantage of the sensitivity its sole permits you have to practice walking on different surfaces, learning to recognise their different characteristic feel.