The Implications of Reduced Contact with Nature for Architectural Design


Yannick Joye

Lab of Applied Epistemology, Ghent University





Evolution in a natural environment has gifted humans with a cognitive module (‘natural module’) that is specialized in processing perceptual and conceptual information about the class of natural things. The existence of such a module has important cultural consequences. It leads to a tendency to create cultural objects that answer the input-conditions of the natural module. During the history of architectural design, this translated in the creation of designs that show remarkable formal and structural similarities with natural elements (e.g. ornamentation). Yet, today, nature is increasingly pushed back, which leads the natural module to become less stimulated and ultimately underdeveloped. An important effect of this understimulation is that people become less interested in creating architectural designs that fulfil the input-conditions of the natural module. It is argued that such an evolution has three negative effects. First, nature consists of a wide variety of shapes, patterns and textures; a decreasing architectural interest in nature entails that a broad range of formal grammars becomes neglected. Secondly, because evolution has linked nature's forms to specific affective states, a broad array of emotional responses towards architectural design are lost. Thirdly, with the gradual exclusion of nature from architectural design and the increase of functionalist architecture, there is a shift towards a relative dominance of functional thinking and functionalist attitudes. Although such postures have their merits in certain contexts, they also prove to have negative effects for human interactions and for ecological contexts. It is proposed that architectural designs that fulfil some of the input-conditions of the natural module provide a counterweight against these (negative) effects.


1. The natural module

Different strands of research indicate that humans are endowed with a ‘module’ or a neural system that is specialized in conceptual and perceptual information about the class of natural things (e.g. plants, animals). This module is a cognitive ‘device’ that is an adaptation to our ancestral evolution and survival in natural environments [1]. A field where the existence of a natural module is debated is research into human ‘folkbiologies’. The notion ‘folkbiology’ refers to the nonscientific way in which people classify natural objects and reason about the natural world. Some research indicates that folkbiologies have certain universal characteristics, which points to a possible innate nature of this faculty. A first finding is that cross-cultural studies show that Western and non-Western individuals classify nature in similar ways, and that this classification roughly corresponds to scientific taxonomies. The typical ‘ranks’ of this universal folkbiological taxonomy are: folk kingdom (e.g. plant-life), life form (e.g. tree), generic species (e.g. oak) and folk specific (e.g. white oak). A second important finding is that the taxonomic types of folkbiologies are consistently ascribed ‘essences’, as opposed to, say, artefacts. The notion ‘essence’ refers to the underlying causal nature of natural objects. Essences are responsible for the behaviour, appearance and ecological preference of natural objects. Importantly, essentialism provides a ground for making inductions about various kinds of natural objects. For example, Scott Atran argues that: ‘… knowing that a Chihuahua and a Saint Bernard share an internal property [essence] is likely to be taken as stronger evidence that all dogs share that property than if only two Chihuahuas are known to share the property’ [2].

The claim for the existence of a natural module finds further support in studies of people with category-specific semantic deficits. Such deficits are most often provoked by brain damage, and translate in impaired semantic knowledge about certain categories of objects. In most cases knowledge about living things is impaired, but cases with a deficit for nonliving things have also been reported. One theory proposes a modular approach to explain such deficits, namely the Domain Specific Account (DSA). According to DSA, knowledge about living things is organized by category [3]. This view implies that specific neural circuits are dedicated to knowledge about different object-categories and that category-specific deficits can occur when this circuitry is damaged. The driving force of this regional specialization was evolution. It is speculated that neural mechanisms are associated with only those things that had evolutionary significance for human beings: animals, vegetable life, conspecifics and possibly tools. With regard to natural objects, research has already suggested neural correlates for such things as fruit and vegetables [4], animals [5] and plants [6].

If the natural module has a genetic component, then knowledge about the associated category of objects will be hard to recover when its neural correlates are damaged. This prediction receives remarkable support from a case study of the patient Adam, described by Farah and Rabinowitz [7]. Adam has experienced brain damage since the day of his birth (‘posterior cerebral artery infarctions’). This damage is associated with a persistent category-specific deficit for living things. More specifically, inquiries indicate that Adam has difficulties in naming pictures about living things, and in retrieving verbal information about this class of objects. Since his deficit has not been recovered by experience, it suggests a human genetic predisposition for knowledge about living things.


2. Cultural consequences of the natural module

According to Sperber and Hirschfeld [8], natural objects (e.g. plants and animals) are the ‘proper input’ of the natural module. Yet, the natural module can also be activated by elements that fulfil its input-conditions, but that do not belong to its proper input. For example, it is quite possible that a stick meets some of the (visual) input-conditions of the natural module, and that it will be recognized as, say, a snake. Sperber and Hirschfeld refer to this type of input as the ‘actual input’ of the natural module. An important observation is that the cultural field often taps the ‘mismatch’ between proper and actual input of cognitive modules. For example, with regard to the face module, Sperber and Hirschfeld argue that ‘[i]n the human cultural environment, a great many artifacts are aimed at the face recognition module. They include portraits, caricatures, masks and made-up faces’. Although such face-like representations are not the proper input of the face module, they contain some crucial visual features by which the face module considers it as actual input.

Because the scope of this paper is the field of architectural design, it is interesting to inquire whether there exist architectural creations that meet up to the visual input-conditions of the natural module, and hence, fall within its actual domain. Indeed, historically, architecture often contains design-elements that share important formal similarities with natural elements. For example, traditional ornament often consists of stylized natural elements, such as leaf-motifs, flowers, fruits, animals, monsters, etc. (fig. 1-3). The presence of (symbolic) nature in architecture also applies to instances of so-called ‘biomorphic’ or ‘zoomorphic’ architecture [9]. For example, it is well-known that vegetative structures are prevalent in Art Nouveau. Similarly, the columns and vaults in Gaudí’s Sagrada Familia look like tree canopies. The same holds for Santiago Calatrava’s BCE Place in Toronto, and for his Orient Station in Lisbon. The symbolic representation of animals is clear in Calatrava’s Milwaukee Art Museum, which can be interpreted as the spreading wings of a bird. Besides such architectural implementations of concrete natural objects, nature can also be evoked by the architectural integration of more abstract or lower-level visual features of natural objects. Think for example of architectural designs with a fractal-like appearance and organization (e.g. Hindu temples, Gothic cathedrals).

It is important to note that the existence of cognitive modules does not come down to biological determinism. It is crucial for such systems to be activated by relevant experiences during developmentally relevant periods. Similarly, some theorists argue that our innate emotive and knowledge relations towards living things are governed by biologically prepared learning rules and that these relations need to be activated by culture, experience and education [10]. Yet, today direct contact with (unspectacular) nature is becoming increasingly difficult in modern urbanized areas. Such a decreasing contact with nature could well lead to the reduction of training and developmental opportunities for the natural module, which could result in the underdevelopment of the latter. Probably, this underdevelopment will translate in devolution of knowledge about nature. An illustration of such devolution is reported by Nabhan and St. Antoine [11]. These researchers studied the knowledge of and attitudes towards nature of two native cultures living near the U.S.-Mexican desert borderland (O’Odham, Yaqui). It was found that the elders had acquired a profound knowledge about the natural world due to their experience with hunting and gathering activities. On the other hand, the grandchildren of the elders, who had reduced contact with nature, showed much less interest in and appreciation of nature.



Figures 1-3: biomorphic and zoomorphic design elements (Y. Joye)





Figures 4-8: some natural patterns (Y. Joye & B. Joye)


3. Architectural consequences of the underdevelopment of the natural module

The underdevelopment of the natural module has several important consequences. For example, if knowledge about and interest in nature is devolving, then it is quite possible that people will be less inclined to protect nature. This could lead to a vicious circle where an increasing loss of nature leads to an increasing disinterest for protecting natural things, which makes the further decline of natural elements even less disturbing. Another effect of the underdevelopment, which is of crucial importance for the further discussion, is the decreasing tendency to create cultural representations that meet up to some of the input-conditions of the natural module. If perceptual and conceptual information about nature becomes increasingly poorer, then the range of possible cultural applications of natural information becomes correspondingly smaller.

It should be noted that this viewpoint finds support in a study by Wolff and colleagues [12]. The authors found that the decline of direct contact with nature during the 20th century has had important negative effects on cultural expressions of nature. In particular, a study of the Oxford English Dictionary, which gives a clear picture of the evolution of word use, indicated that terms referring to ‘tree’ evolved from the 16th until the 19th century. Yet, from the 20th century onwards, the use of such terms devolved, and their application lost precision. A similar devolution was observed for other (folk)biological concepts (e.g. bird, grass, flower), while several nonbiological terms evolved during this period (e.g. books, clothes, furniture).


Although (apparently) no such research exists for the field of architecture, it is plausible that the underdevelopment of the natural module will lead to a declining presence of references to nature within architectural design. While it is true that nature has been related to the architectural practice in many ways (e.g. the argument that functionalism is similar to natural growth processes [13]), the following sections will focus on the various kinds of formal representations and interpretations of natural objects within architecture. More specifically, it will be argued that devolution of nature within architecture leads to three types of impoverishments of the architectural practice. Because the first two types of impoverishment are closely interrelated, they will be treated in the same section.


3.1. The impoverishment of formal grammars and the loss of the associated affective correlates

A first effect of the underdevelopment of the natural module is that the range of possible formal grammars that are applied to architecture becomes poorer. Nature shows a very wide and rich diversity of patterns, textures and contours (fig. 4-8). Yet, Peter Stebbing [14] has argued how only a limited set of organizational constituents (contrast, pattern, symmetry, proportion, unity) underlie these shapes. These constituents form a kind of compositional grammar that can be used for creating artwork. Similarly, Simon Bell [15] holds that a limited number of core patterns can be recognized in the seemingly unlimited number of natural forms: spirals, meanders, branches, explosions, packing and cracking.

In human languages, only a limited set of grammatical rules and phonemes underlies the unlimited number of possible linguistic expressions. Similarly, nature’s formal grammars and compositional rules do not constrain artistic creativity, but are, on the contrary, a prerequisite for creativity, because they allow one to create an endless set of formal permutations. Yet, due to the underdevelopment of the natural module, it is probable that interest in nature as a creative source will decline. This could entail that artists and architects will show increasingly less interest to learn about nature’s formal grammars and about its compositional rules. Such a trend seems already ongoing in different modernist urban environments, which often contain only one dominant architectural style: they are governed by Euclidean geometry and stripped of every ornament, detailing and colour.

It is quite possible that people will be able to adapt to the expression of a more limited set of forms in architecture, and that they will lose insight into this situation. Because aesthetic tastes are not exclusively determined by evolutionary constraints, it is also quite possible that (some) people will genuinely like such type of uniform environments. Yet, these observations cannot be sufficient to justify the loss of certain formal grammars in architecture. The reason is that an increasing dominance of uniform modernist environments will probably have a number of psychological and physiological ‘costs’. These are due to the fact that, under evolutionary pressures, nature’s forms have become associated with a broad range of emotions, ranging from fear to excitement. In our ancestral world, such associations were adaptive because they motivated the (human) organism to undertake a suitable response towards a certain stimulus [16]. For example, a predisposition to react fearfully towards certain types of snakes was adaptive because it motivated to avoid close contact with the snake. This association of natural objects with specific emotions entails that the natural module will be linked to neural areas or ‘modules’ [17] that are specialized in affective or emotional states. A crucial observation is that by integrating formal references to nature within architecture, these emotions can be tapped. Due to their similarity with natural elements, such designs or design elements will fulfil certain visual input-conditions of the natural module, and will consequently activate associated affective states. When the application and interpretation of nature’s forms to the field of architecture decreases, this can also lead to a reduction of the range of possible emotional attitudes that are associated with architectural environments. This is the second type of impoverishment.

Because the link between ‘naturalness’ and (positive) emotional states is being studied within the field of environmental psychology, it is useful to mention some of its key findings. Several studies indicate that humans are aesthetically attracted to vegetative elements (e.g. flowers, trees) and water-features. This is because these elements were important food resources, and because they offered our ancestors retreats from threats and prospects on the surrounding landscape [18-19]. Apart from inducing positive aesthetic responses, some natural things are also found to have a positive impact on different aspects of human functioning. According to Roger Ulrich [20] encounters with unthreatening nature (vegetation, water-features) have a stress-reducing effect, and promote postures of intake and attention. Similarly, Stephen Kaplan [21] argues that nature can restore the capacity to direct attention. These viewpoints are supported by elaborate and convincing empirical investigations [22-23]. There is evidence that unthreatening animals have a similar positive impact on human functioning. Animals are found to reduce stress; lead to less general health problems; lower systolic blood pressure and cholesterol; and are associated with higher survival chances after myocardial infarctions [24]. Similarly, Katcher and Wilkins [25] argue that introducing animals to autistic children and to persons with chronic brain damage can ameliorate attention, social responsiveness, positive emotions and speech.


3.2. Dominance of functionalist thinking and attitudes

In order to discuss the third type impoverishment resulting from the devolution of ‘naturalistic’ elements in architecture, it is necessary to consider a theory about the organization of concepts in semantic memory. This theory is coined the Sensory Functional Theory (SFT), and it claims that knowledge in the semantic system is organized into subsystems that each process some type or modality of knowledge [26-27]. The central claim of the Sensory Functional Theory is that the recognition of the category of living things is differentially dependent on the ‘perceptual’ semantic subsystem. This means, for example, that the concept ‘zebra’ will activate such perceptual concepts as ‘has black and white stripes’. On the other hand the ‘functional’ semantic subsystem is most crucial for recognizing nonliving things. According to this view, the concept ‘key’ will activate such functional concepts as ‘used for locking’ (table 1).



Table 1: Schematic representation of SFT

This view could have some subtle, though important consequences. The presence of nonliving things, and especially purely functional architectural design, is ever increasing in the human living environment. This entails that functional semantic networks are becoming ever more important and dominant for processing the elements that constitute our surroundings. Such a dominance of functional concepts could promote a posture of functional thinking and behaviour, which further strengthens beliefs in the utility and value of functional objects and architectural design. Although functional attitudes have its merits in certain contexts, they can be harmful for our relations towards others and towards the natural world.

Possibly, integrating naturalistic elements in architecture can provide a counterweight against the increasing dominance of these functional semantic networks and their associated epistemological attitude. By having some key similarities with living things, such type of design will also activate semantic networks that are not predominantly related to functionality. Instead, they could activate areas that process the unique perceptual features of objects. This could result in an attitude that is especially relevant when it comes to the human relation with nature. While nature is increasingly valued from a purely functionalist perspective, ‘naturalistic’ design could contribute to learning to be attentive to nature’s perceptual qualities. This could help in creating a mindset where nature will also be enjoyed for its own perceptual presence, and not for the functions it could fulfil. This entails a robust form of environmental education. Note furthermore how such a way of thinking can also prove to be of value for the field of art and design, where perceptual concepts often play a key role.


4. Naturalistic forms in architecture: different levels of abstraction

The previous argument underscores the importance of integrating references to natural form in architecture. Such integrations can take on different levels of abstraction. Literally copying concrete natural elements in architectural design (e.g. traditional ornament) will probably meet up to the input-conditions of the natural module due to the important formal overlap with real natural objects. Admittedly, today such imitations will not be considered as very successful, because the associated emotional states will probably be inhibited by certain higher-order or ‘cultural’ concepts (e.g. ‘kitsch’). An alternative would be to implement more schematic representations of natural elements in architecture. These would no longer be exact copies, but artistic interpretations that still contain some global visual similarities with regard to the original natural object (e.g. Calatrava’s bird-like structure for the Milwaukee Art Museum). These similarities make it probable that these designs or design elements will be considered as actual input of the natural module. The situation is somewhat similar to abstract or schematic representation of faces (J), which activate the face module, despite their high level of abstraction. Yet, still more architectural variations could be created by applying and combining abstract geometrical features of natural elements to architectural designs. Although such designs will not be recognized as being similar to concrete natural objects (e.g. a bird) they will still activate early visual subsystems of the natural module, which are specialized in natural-like perceptual features. Due to these activations, such creations could still evoke semantic associations of ‘naturalness’, by which they could be accompanied by certain emotional states (see section 3.1). In the following two sections two types of ‘shape grammars’ are presented that are typical of natural objects.


4.1. Fractal geometry

An inspection of the formal appearance of evolutionary relevant natural objects (e.g. trees and plants) reveals that their shape is governed by fractal geometry [28] (see also fig. 4-8). An essential characteristic of fractal-like structures is that (statistically) similar details recur on different scales of magnitude. Within fractal geometry, this scale invariance contributes to the complexity of a fractal pattern and is quantified in terms of the fractal dimension D. Contrary to Euclidean geometrical objects, the fractal dimension of a fractal curve is not an integer. For fractals in the plane, the fractal dimension lies between the first and the second dimension, resulting in a value between 1 and 2. The reason is that it fills more space than a line, while it does not fill the entire plane. For fractals in space, the fractal dimension lies between 2 and 3 [29].

The naturalness of fractals cannot be reduced to the theoretical possibility of describing natural patterns in terms of fractal geometry. Humans also interpret fractals as being closely related to the shapes of natural objects. For example, a qualitative study shows that primary schoolchildren found fractal patterns to be similar to such things as: ‘“trees, flowers, dragons, Aboriginal paintings, pathways, feathers, insects, elephants”; “trees, zippers, planets, sea horses and other animals in the sea”; … “leaves, root systems, flowers, star constellations, solar systems, and star fish and other creatures” …’ [30]. The relation between judgements of ‘naturalness’ and fractals has also been empirically studied by Hagerhall and colleagues [31]. These researchers found a systematic correlation between the aesthetical preference of landscape silhouettes and their respective fractal dimensions. Because naturalness is found to be a predictor of aesthetic preference (see section 3.1), this suggests that fractal dimension could be a constitutive part of the naturalness of particular scenes.

The previous findings indicate that the naturalness of some objects is to a certain extent determined by the presence of fractal geometry. Interestingly, there are preliminary indications that fractal patterns can trigger some of the (positive) affective states that are associated with natural elements. Some empirical research reveals that such patterns have an aesthetic and stress-reducing value. Yet the strength of these affective reactions seems to vary as a function of the fractal dimension. For example, there are indications that subjects do not attribute highest aesthetic preference to patterns with the lowest and highest fractal dimension [32-35]. Instead, there is a tendency to prefer patterns with an intermediate fractal dimension, ranging from 1.3 to 1.5. Similarly, a preliminary study indicates that the fractal patterns that are most effective in stress-reduction also fall within this range of D values [36]. A possible explanation is that this fractal dimension corresponds to the complexity of natural elements and settings that offered our ancestors important survival opportunities.


4.2. Naturalness and curves

Animals have a typical shape and structure, but often do not show the scale invariance that is characteristic of fractals patterns. But which geometric features are important for recognizing such type of objects? An indication is provided by research that suggests that curved information is important for identifying certain classes of objects. For instance, some studies argue that the deficit for recognizing faces of certain prosopagnosic patients is due to problems with processing curves [37] and curved surfaces [38]. Because of the evolutionary importance of recognizing conspecifics and facial expressions, and because this recognition is dependent on making subtle differentiations of curved features and volumes, possibly a module could have evolved that is specialized in curved volume description [39]. It is quite possible that not only the face recognition module taps this module, but also other systems that rely on coding curvature. Importantly, measurements of animal contours reveal that these have a high degree of curvature, as opposed to the rectilinearity of a lot of nonnatural objects (e.g. chair) [40]. Correspondingly, damage to this curvature module does not only result in prosopagnosia, but leads to subtle difficulties in processing and recognizing certain nonface objects that are also characterized by curves, such as animals. Although the recognition by the natural module of certain stimuli as ‘natural’ depends on a variety of features (e.g. higher-order concepts such as ‘has legs’), these findings suggest that the presence of curves is a contributing factor to the naturalness of certain objects.

If there is a certain correlation between some natural kinds (e.g. animals) and curves, then are there also certain emotions associated with the latter? This question cannot be answered straightforwardly, because only little research has been conducted into the relation between curves and emotions. Yet, it must be admitted that the perennial presence of curved patterns (spirals, scrolls, meanders) is an important indication for the aesthetic value that people attach to such patterns [41]. Maybe this aesthetic attraction is due to the fact that such patterns evoke natural objects. Sometimes, the emotional value of curved contours is also related to the importance of viewing faces. For example, Peter Stebbing [42] tries to explain the aesthetic attraction of the so-called ‘asymmetrical curve’. This pattern is the contour of a woman’s face, viewed from the perspective of a baby that is held in its mother’s arms. Because babies often look at their mother’s face, they are imprinted with her cheek curve. Due to feelings of love, comfort, care and security, this pattern is loaded with a positive emotional association. Consequently, in adult life, the cheek curve acts as a biological releaser that elicits positive emotional states and aesthetic attraction.

Further investigations into the emotional tone of curved lines are mentioned by Nancy Aiken [43]. Aiken describes how in early studies by Lundholm [44] and Poffenberger and Barrows [45] subjects had to associate different types of lines with various affective adjectives (e.g. ‘sad’, ‘quiet’, ‘furious’, ‘harsh’, etc.). These experiments revealed that angled and curved lines were releasers of different categories of feeling tones. This conclusion is supported by a more recent experiment by Johanna Üher [46]. She found that angled lines were associated with antagonistic characteristics (e.g. ‘aggressive’, ‘hostile’, ‘harsh’, ‘irritated’, etc.), while curved lines were matched with affiliative characteristics (‘peaceful’, ‘friendly’, ‘gentle’, ‘balanced’, etc.). This indicates that curves evoke more positive emotions (e.g. security), while angles are related to more negative emotions (e.g. fear). The antagonistic character of angled lines is also evident from an experiment by Richard Coss [47]. Coss compared the effect of pointed and rounded contours on the physiological state of ten men. He found that angled shapes elicited more arousal, were more provocative and were more attention-grabbing than rounded forms. The latter were experienced as less arousing and attractive, but will probably give rise to more ‘harmonious’ and ‘peaceful’ emotions. Coss argues that the arousing properties of angles are due to the danger associated with piercing forms, with which humans were confronted during their evolutionary history. Despite this explanation, neither Coss nor the aforementioned authors clarify the reasons for the affiliative nature of rounded forms.

5. Discussion


Due to the gradual decrease of direct contact with nature in Western (and westernized) societies, the natural module gets increasingly less opportunities to get trained and to develop. It was argued how this underdevelopment could lead architectural designers to become less interested in including formal references to nature into their creations. Maybe the strongest opposition against such integrations has been expressed by Adolf Loos. In ‘Ornament and Crime’ [48] he described the use of ornamentation as a sign of cultural and intellectual degeneracy, having negative effects on human wellbeing. Instead, he defended an aesthetic purism that banned the use of ornamentation. Because ornaments often contain ‘symbolic’ nature, the above argument proposes that Loos’ extreme viewpoint could lead to three interrelated types of ‘impoverishment’. It possibly entails a reduction of the range of possible formal grammars applied to architecture; it leads to an impoverished emotional relation with the built environment; and it contributes to a tendency of ‘functional’ thinking and attitudes. It was hypothesized that these effects underscore the importance of including formal evocations of nature in architectural designs. These evocations can range from imitations of concrete natural elements (e.g. flowers) to combined applications of abstract formal features that are characteristic of naturalness (e.g. fractals and curves). It should be noted that digital design and visualization techniques have greatly facilitated the creation of such ‘biomorphic’ designs and the exploration of non-standard geometrical shapes. Yet, it has not been argued that such type of architecture should replace current (modernist and postmodernist) architecture. On the contrary, the central argument of this paper is essentially pluralistic, and entails that different types of architecture, and hence, different formal grammars should be allowed to coexist. While some types of architecture are more responsive to cultural ideas, the type of design that is discussed in this paper fulfils conditions that are guided by a shared human evolution in the natural world.




[1]     Tooby, J. & Cosmides, L. (1992) The Psychological Foundations of Culture, in Barkow, J.H., Cosmides, L. & Tooby, J. [Eds] The adapted mind. Evolutionary psychology and the generation of culture. Oxford University Press, pp. 19-136.

[2]     Atran, S. (1995) Causal constraints on categories and categorical constraints on biological reasoning across cultures, in Sperber, D. et al [Eds] Causal cognition. A multidisciplinary Debate. Clarendon Press, pp. 205-233.

[3]     Caramazza, A. & Shelton, J.R. (1998) Domain-specific knowledge systems in the brain: the animate-inanimate distinction, Journal of Cognitive Neuroscience, Vol 10, no 1, pp. 1-34.

[4]     Samson, D. & Pillon, A. (2003) A case of impaired knowledge for fruit and vegetables, Cognitive Neuropsychology, Vol 20, no 3-6, pp. 373-400.

[5]     See note [3]

[6]     Kawashima, R. et al (2001) Different neural systems for recognizing plants, animals, and artefacts, Brain Research Bulletin, Vol 54, no 3, pp. 313-317.

[7]     Farah, M.J. & Rabinowitz, C. (2003) Genetic and environmental influences on the organisation of semantic memory in the brain: is “living things” an innate category? Cognitive Neuropsychology, Vol 20, no 3-6, pp. 401-408.

[8]     Sperber, D. & Hirschfeld, L.A. (2004) The cognitive foundations of cultural stability and diversity, Trends in Cognitive Science, Vol 8, no 1, pp. 40-46.

[9]     Aldersey-Williams, H. (2003) Zoomorphic. New Animal Architecture. Laurence King.

[10]   Ulrich, R.S. (1993) Biophilia, Biophobia, and Natural Landscapes, in Kellert, S.R. & Wilson, E.O. [Eds] The Biophilia Hypothesis. Island Press, pp. 73-137.

[11]   Nabhan, G.P. & St. Antoine, S. (1993) The loss of floral and faunal story: the extinction of experience, in Kellert, S.R. & Wilson, E.O. [Eds] The Biophilia Hypothesis. Island Press, pp. 229-250.

[12]   Wolff, P. et al (1999) Evolution and devolution of folkbiological knowledge, Cognition, Vol 73, pp. 177-204.

[13]   Häring, H. (1978) Approaches to form, AAQ, Vol 10, no 1, p. 21.

[14]   Stebbing, P. (2004) A Universal Grammar for Visual Composition? Leonardo, Vol 37, no 1, pp. 63-70.

[15]   Bell, S. (1999) Landscape. Pattern, Perception and Process. E & FN Spon Press.

[16]   Ulrich, R. (1983) Aesthetic and affective response to natural environment, in Altman, I. & Wohlwill, J.F. [Eds] Human Behavior and Environment Volume 6. Plenum Press, pp. 85-125.

[17]   Mineka, S. & Öhman, A. (2002) Phobias and preparedness: the selective, automatic, and encapsulated nature of fear, Biological Psychiatry, Vol 52, pp. 927-937.

[18]   Orians, G. (1980) Habitat selection: general theory and applications to human behaviour, in Lockard, J.S. [Ed] The evolution of human social behaviour. Elsevier, pp. 49-66.

[19]   Appleton, J. (1975) The experience of landscape. Wiley.

[20]   See note [10]

[21]   Kaplan, S. (1995) The restorative benefits of nature: toward an integrative framework, Journal of Environmental Psychology, Vol 15, no 3, pp. 169-182.

[22]   Hartig, T. et al (2003) Tracking restoration in natural and urban field settings, Journal of Environmental Psychology, Vol 23, no 2, pp. 109-123.

[23] Ulrich, R.S. et al (1991) Stress recovery during exposure to natural and urban environments, Journal of Environmental Psychology, Vol 11, pp. 201-230.

[24] Frumkin, H. (2001) Beyond toxicity. Human health and the natural environment, American Journal of Preventive Medicine, Vol 20, no 3, pp. 234-240.

[25]   Katcher, A. & Wilkins, G. (1993) Dialogue with animals: its nature and culture, in Kellert, S.R. & Wilson, E.O. [Eds] The Biophilia Hypothesis. Island Press, pp. 173-197.

[26]   Crutch, S.J. & Warrington, E.K. (2003) The selective impairment of fruit and vegetable knowledge: a multiple processing channels account of fine-grain category specificity, Cognitive Neuropsychology, Vol 20, no 3-6, pp. 355-372.

[27]   Farah, M.J. & McClelland, J. (1991) A computational model of semantic memory impairment: modality specificity and emergent category specificity, Journal of Experimental Psychology, Vol 120, no 4, pp. 339-357.

[28]   Hirst, B. (1994) Fractal Landscapes. Cornerhouse Publications.

[29]   Voss, R.F. (1988) Fractals in nature: From characterization to simulation, in Peitgen, H.O. & Saupe, D. [Eds] The Science of Fractal Images. Springer Verlag, pp. 21-70.

[30]   Geake, J.G. (1992) Fractal computer graphics as a stimulus for the enhancement of perceptual sensitivity to the natural environment, Australian Journal of Environmental Education, Vol 8.

[31]   Hagerhall, C.M. et al (2004) Fractal dimension of landscape silhouette outlines as a predictor of landscape preference, Journal of Environmental Psychology, Vol 24, no 2, pp. 247-255.

[32]   Abraham, F. D. et al (2003) Judgements of time, aesthetics, and complexity as a function of the fractal dimension of images formed by chaotic attractors. ms2.htm

[33]   Aks, D.J. & Sprott, J.C. (1996) Quantifying aesthetic preference for chaotic patterns, Empirical studies of the arts, Vol 14, no 1, pp. 1-16.

[34]   Spehar, B. et al (2003) Universal aesthetic of fractals, Computers & Graphics, Vol 27, no 5, pp. 813-820.

[35]   Sprott, C. (1996) The Computer Artist and Art Critic, in Pickover, C.A. [Ed] Fractal Horizons: The Future Use of Fractals. St. Martin’s Press, pp. 77-115.

[36]   Taylor, R.P. et al (2003) Perceptual and Physiological Responses to the Visual Complexity of Pollock's Fractal Dripped Patterns. To be published in: The Journal of Non-linear Dynamics, Psychology and Life Sciences.

[37]   Kosslyn, S.M. et al (1995) The perception of curvature can be selectively disrupted in prosopagnosia, Brain & Cognition, Vol 27, pp. 36-58.

[38]   Laeng, B. & Caviness, V.S. (2001) Prosopagnosia as a Deficit in Encoding Curved Surface, Journal of Cognitive Neuroscience, Vol 13, no 5, pp. 556-576.

[39]   See note [38]

[40]   Levin, T.L. et al (2001) Efficient visual search by category: specifying the features that mark the difference between artifacts and animals in preattentive vision, Perception and Psychophysics, Vol 63, no 4, pp. 676-697.

[41]   Wilson, E. (2001) 8000 years of ornament. The British Museum Press.

[42]   Stebbing, P. (1999) The beauty of the mother’s smile, in Soddu, C. [Ed] Proceedings of the 2nd International Conference GA ’99. Editrice Librerie Dedalo.

[43]   Aiken, N.E. (1998) The biological origins of art. Praeger.

[44]   Lundholm, H. (1921) The affective tone of lines: experimental researches, The Psychological Review, Vol 28, p. 60.

[45]   Poffenberger, A.T. & Barrows, B.E. (1924) The feeling value of lines, Journal of Applied Psychology, Vol 8, pp. 187-205.

[46]   Üher, J. (1991) On zigzag designs: three levels of meaning, Current Anthropology, Vol 32, no 4, pp. 437-439.

[47]   Coss, R.G. (2003) The role of evolved perceptual biases in art and design, in Voland, E. & Grammer, K. [Eds] Evolutionary Aesthetics. Springer-Verlag, pp.69-130.

[48]   Loos, A. (1999) Ornament and Crime, in Conrads, U. [Ed] Programs and Manifestoes of 20th-Century Architecture. MIT Press, pp. 19-24.