Seleção de espécies medicinais entre comunidades locais da caatinga e da floresta atântica

Abstract

The selection of plants for therapeutic purposes by human groups is not random. Although people have access to a wide variety of vegetables in their environments, only a small portion of these species are included in local pharmacopoeias and some use behaviors have recurred for human groups from different regions and cultures. However, little is known about the reasons that lead to the selection of certain species to the detriment of others. Based on the premise that human behavior is a result of its biological and cultural "nature", the present project aims to investigate the environmental factors that determine or influence certain patterns of plant use for medicinal purposes. In order to do so, this work aimed to transpose into ethnobotany a concept analogous to Ecological Equivalence, hereafter called Utility Equivalence, and uses it as an analytical tool in the search for common criteria for the selection of medicinal plants. While the first concept, derived from traditional ecology, refers to distinct species that perform similar ecological functions in distinct ecosystems, Utilitarian Equivalence applies to different species of different socioecological systems (sociocultural + ecological) used for the same purposes. therapies. Starting from this idea, we have the occurrence of 'equivalent pairs', that is, pairs of plants with high rates of overlapping medicinal use. In the present studo, this concept was applied for medicinal use. In this sense, we can consider that access to equivalent medicinal species provides the ideal scenario to seek common selection criteria, since it allows identifying the shared characteristics among the equivalent pairs and consequently the main types of perceptions or stimuli that led to inclusion of such species in local pharmacopoeias. Thinking in this way, this thesis is divided into three main thematic axes: 1) the role of taxonomic affiliation on the establishment of utilitarian equivalence and utilitarian redundancy; 2) the role of chemical composition in the selection of medicinal resources, using as a proxy the utilitarian equivalence and utilitarian redundancy among plants with the same class of chemical compound; 3) How utilitarian equivalence and utilitarian redundancy can be influenced by environmental perception in terms of organoleptic characteristics. The idea was to verify if the equivalent pairs and redundant pairs are similar in terms of chemical, organoleptic, perceived availability and taxonomic affiliation. As results, there was a great influence of taxonomic affiliation, so that plants of the same genus are twice as likely to be equivalent to plants of different genera. As for chemical inluence, only the class of alkaloids was able to favor the overlap of uses between plants with this same compound, which perhaps reflects a greater greater specificity of this compound in relation to the others. When we are faced with the perceptual question, we observe that the flavor was only able to lead to overlapping uses when considered as a medical system, that is, utilitarian redundancy is affected by this variable and utilitarian equivalence is not. In view of the evidences demonstrated and of what was discussed, we perceive that human populations have different beliefs, meaning and social organizations for the understanding of health and disease. However, the environment poses some challenges and communities can find similar ways of dealing with those challenges. In addition, the utility equivalence model allows us to observe how people from different regions of the world have appropriated natural resources and can be used to investigate biological and cultural factors.