How can we imagine that an inch in the tail of the peacock, or ¼ inch in that of the Bird of Paradise, would be noticed and preferred by the female? Alfred Wallace, letter to Charles Darwin, March 1868.
regard to sexual selection. A girl sees a handsome man, and without
observing whether his nose or whiskers are the tenth of an inch
longer or shorter than in some other man, admires his appearance
and says she will marry him. So, I suppose, with the pea-hen .....
Charles Darwin, letter to Alfred Wallace, March 1868.
The archaeological record of the last Ice Age, particularly after about 40,000 years ago, documents the emergence of clearly symbolic behaviour, including burials that were furnished with grave goods, the invention of parietal and portable representational art, the use of items of body ornamentation and possible instances of numerical or calendrical notation (Pfeiffer, 1982). This kind of material cultural evidence has informed and stimulated the discussion of the evolution of modern human cognitive abilities, but there is also an important aesthetic dimension to human culture, and as Kaplan (1992) has emphasised, evolutionary explanations of human aesthetic preferences benefit from integrated approaches that consider both cognitive and emotional responses. On both theoretical and empirical grounds it is likely that human emotional adaptations evolved much earlier than strictly symbolic capacities, given that 99% of the five million year timespan of hominid evolution preceded the emergence of material evidence for symbolic behaviour. Thus the study of human aesthetic preferences may provide a window into an extensive epoch in the early evolution of the human psyche.
In this paper I review some human visual aesthetic preferences that may have originated in our species distant evolutionary past. These preferences include evolved responses to natural landscapes, symmetry preferences, and criteria of facial attractiveness. In the discussion that follows I employ a very general definition of aesthetics, best summarised as "mental appreciation of the shape or embellishment imposed on raw materials" (cf. Dissanayake, 1992), in which the term "appreciation" primarily denotes an involuntary emotional response to a stimulus, rather than the deliberate intellectual stance adopted by the modern professional or philosophical aesthete.
An innate human preference for visual landscapes that have properties resembling those of savanna habitats (i.e. low-relief, sparsely-wooded tropical grasslands: Figure 1a & b) has been attributed to selection pressures operating during early human evolution (Balling & Falk, 1982; Orians & Heerwagen, 1992). According to Orians and Heerwagen, present-day humans express a rapid and often unconscious affective response to those general properties of a landscape that are perceived on initial visual encounter. Preferred landscapes are those containing features indicative of environmental conditions favourable for survival, such as an abundance of subsistence resources or a minimal threat from predators. The preference for savanna-style visual landscapes is most strongly expressed in children (Balling & Falk, 1982), and is also manifest in the deliberate design of artificial landscapes as exemplified by modern (i.e. post-Renaissance) ornamental parks and gardens (Kaplan, 1992). A more specific hypothesis of landscape preference stems from "prospect-refuge theory", which predicts that within a given landscape preferred locations are found at interfaces between prospect-dominant and refuge-dominant areas (Appleton, 1996). These vantage points combine unimpeded visual prospects with a ready opportunity for concealment and/or withdrawal to a safe refuge. Thus a treeless landscape is less visually attractive than a habitat containing isolated trees that can provide opportunities to hide or escape from potential predators.
Exponents of the human preference for savanna-like habitats have reasoned that the human environment of evolutionary adaptiveness (EEA) was located in the Plio-Pleistocene savannas of sub-Saharan Africa. It has been argued that habitual occupation of the savanna biome by Australopithecus and early species of Homo provided an extended period of selection for the reinforcement of intuitive preferences for certain topographic, botanical and faunal features of the savanna landscape (cf. Orians & Heerwagen, 1992: 556). However, this scenario of human evolution is over-simplified, and there is an increasing consensus among palaeoanthropologists that there is no single unitary environment to which earlier human species were optimally adapted (Foley, 1996). Ardipithecus ramidus and Australopithecus anamensis, the earliest known hominids, show morphological adaptations to arboreal substrates (White et al, 1994; Leakey et al., 1998) and the fossils of Ardipithecus ramidus have been recovered from depositional contexts characteristic of closed canopy woodland rather than open savanna (WoldeGabriel et al., 1994). Furthermore there is also an extensive and more recent history of human occupation of non-savanna biomes, especially after 1.8 million years ago when species of Homo first appear in higher latitude regions of Asia and Europe.
Evidence of heterogeneity in hominid landscape preferences has been sought in studies of the geological and ecological contexts within which hominid fossils have been discovered, in an attempt to delineate ecological differences between hominid species (Behrensmeyer, 1978; White, 1988). There is a substantial and difficult taphonomic problem here: are the habitats that are conducive to the deposition and preservation of hominid fossils representative of the environments to which the hominids were originally and optimally adapted? Whites (1988) analysis of the relative frequencies of Homo and Australopithecus fossils in different African palaeoenvironments failed to confirm earlier suggestions that Homo fossils were relatively more common in river bank and lake margin settings. However, most of the East and South African Pleistocene hominid sites have palaeoenvironmental profiles indicating a mosaic habitat, with a mixture of flora and fauna that are individually adapted to open grassland, woodland and proximity to water. This provides indirect support for the prospect-refuge theory of human landscape preference, as the palaeoenvironmental evidence would be expected to show a mixture of habitat types if hominid occupation sites were preferentially located at habitat interfaces.
Thus if there is an evolved human psychological preference for savanna habitats this is unlikely to have been inherited as a phylogenetic legacy from a much earlier (i.e. australopithecine) phase of human evolution. The palaeoecological evidence, though sparse, suggests that Lower Pleistocene hominids favoured either closed woodland (Ardipithecus) or mosaic habitats (Australopithecus and early Homo). Furthermore, in living primates there are instances of divergence of substrate and habitat preference between closely-related species (for instance, both arboreal and terrestrial species exist within each of the genera Cercopithecus and Macaca), suggesting that evolved environmental preferences in primates are typically species-specific adaptations rather than plesiomorphic traits inherited by all members of a genus. This raises the possibility that the savanna landscape preference that characterises modern humans arose relatively recently, perhaps coinciding with the emergence of anatomically modern Homo sapiens. One model of the origin of anatomically modern humans places the crucial speciation event that gave rise to our species in sub-Saharan Africa, at about 100,000 years ago (Stringer & Andrews, 1988). It is therefore possible that the preference for savanna habitats emerged when modern humans were confined to these regions of Africa, prior to their expansion to other regions of the world during the Upper Pleistocene.
An earlier version of this paper was presented at a conference on the Evolution of Mind, organised by the Hang Seng Centre for Cognitive Studies, University of Sheffield, in June 1998.
Andrew Chamberlain can be contacted at: Department of Archaeology & Prehistory, University of Sheffield, Northgate House, West St, Sheffield S1 4ET. mailto:firstname.lastname@example.org
Anthony Napoleon, the author of Awakening Beauty: An Illustrated Look at Mankind's Love and Hatred of Beauty, is a psychologist who has spent many years studying beauty and its impact upon both individuals and society. He has worked with both cosmetic surgery patients and beauty pageant contestants as well as conducting original research into the field. Awakening Beauty is an unprecedented exposé on the subject of beauty. It is both entertaining and thought provoking, a combination that is as unique as it is telling about the author's approach to the subject of this book. The reader is taken backstage into the worlds of beauty pageants, plastic surgery, trophy wives, murderous rage, wardrobe, makeup, Bill Clinton, the events of September Eleven and other provocative topics where beauty has had its effect. Awakening Beauty invites the reader into a world that is as interesting as it is frightening. Readers are transformed as the author shepherds them from their world into his unique perspective and expertise on beauty. Awakening Beauty includes over one hundred tantalizing photographs and illustrations. Awakening Beauty is a compendium of some of the most interesting facts in print. The subject matter of the book along with the author's unique approach to it makes this book a "must read." Get ready to re-think everything you thought you knew about beautiful women and physical attractiveness.