Má adaptação em sistemas médicos locais baseados em plantas : processos que favorecem o estabelecimento de tratamentos ineficientes em populações humanas

Abstract

The aim of this thesis is understand which mechanisms are related with the occurrence and establishment of maladaptative cultural traits in local medical systems. In this way, two main investigation ways were adopted: 1) temporal evaluation of the knowledge sharing of plant treatments that does not have pharmacological efficiency; 2) investigation of mechanisms that favour the use of medicinal plants in association with allopathic medicines. The data were collected with interviews made in 2007 and 2016 in the Carão rural community located in Northeast of Brazil. The identification of pharmacological effect was made with a systematic review using each name of plant species that were cited in the community. Multilevel longitudinal linear models and multilevel logistic regressions were used to anlyse the data. Versatile plants have the tendency to be established in the local medical system, even if they did not have chemical efficiency. This may indicate that versatile plants have a local "status" of effectiveness, which could bias the copy of that information. In this case, generalizations may be leading people to copy inefficient treatments linked to versatile plants. In realtion to the frequency of diseases, we found that treatments linked to frequent illnesses tend to be more shared over time, probably due to the need to cure these health problems, which promotes a greater number of copy events. Moreover, overlapping use with allopathic drugs explains the greater sharing of non-efficient treatments, evidencing, perhaps, that the simultaneous use of allopathic and medicinal plants allows the establishment of maladapted traits by hiding the inefficiency of the plant. Finally, it can be seen that the consortium use of medicinal plants and allopathic drugs occurs in sensitive parts of the medical system, in the case of treatment of chronic, severe and frequent diseases. So, this combination of uses could be motivated by the need to ensure the cure of important diseases. However, use plants and allopactic medicines in consortium makes it difficult to recognize the real cause of the cure, which may lead to the establishment of maladapted cultural traits.