Ecological Niche Theory: Non-traditional Urban and Rural Human Populations

Abstract

ABSTRACT Statistical samples from urban and rural non-traditional populations at Piracicaba, SP, Brazil, are studiedin terms of human ecological fitness to his own environment. Ecological fitness was measured by Body Mass Index(BMI) with a demographic approach. Niche amplitude was estimated by Levins index. An economic classification wasalso elaborated. The highest level income families include rare food items and relative narrowing of food niche. Bothpopulations use the same five food items more frequently: rice, beans, meat, bread, and coffee. According to BMI,these foods are not adequate: overweight and obesity mean that both populations are not ecologically fitted to theirenvironment. The three joint approaches (ecological, economical and population nutritional status) have shown tobe adequate for human ecological studies on modern ways of life. They also made it clear that economical factors areinconclusive for food choices. INTRODUCTION In 2007, about half of world human populationwas already living in urban environments (RNU2007). Most of them and an expressive part ofrural population were living non-traditional waysof life. The current way of life of humans causesmore impact over the environment and, also,allows the proliferation of specific diseases,affecting human life, interfering in fitness, suchas overweight and obesity, which nowadayscharacterize a global epidemic event (WHO 2000,2009). Human ecology, both as science and asstudy program (Begossi 1993), cannot avoidfacing this context. It is necessary to proposeand to test multi-disciplinary scientific approaches,in order to study these complexes aspects incurrent Human Ecology.Food choices and food intake are the mostimportant interactions between population andits environment. The success of these interactionsis very important for ecological fitness ofa particular population. For non-traditionalpopulation, perhaps, economical factors can bethe strongest ecological influences on foodchoices (Begossi et al. 2002). In this paper,ecological human fitness and ecological foodniche were employed associated to an economicclassification, in order to perform a human-ecological study of urban and of rural populations,both presenting modern ways of life.The ecological concept, as proposedby Hutchinson (1957), expresses the relationshipof an individual or a population to all aspects ofits environment. Among several aspects, foodselectivity analyses shows itself as a nichedimension measure. This concept was appliedfirst to human population by Hardesty (1972).Studies on the relationship between humanpopulation and environmental resources haveemployed concept (Adams 2002; Hanazakiand Begossi 2004; Cavallini and Nordi 2005;Silva and Begossi 2009). However, studiesapproaching concept applied to humanurban populations are not found. Laland et al.(2007), employ niche construction concept,similar dimensions to Hardesty's concept, whichwas applied to urban environments. Accordingto these authors, the niche construction is aresult from relationships between the organismand its environment, which comprehends itsmetabolism, activities, and choices. They includelearning and culture in studying ecological nicheon human populations. Shenegyan and Zhiheng