ABSTRACT Among the recently discussed evolutionary issues on medical systems, one of the most controversial issues is the replacement of local medical systems with the biomedical system. Our study investigates the hybridization of two medical systems and the role that the perception of incidence and severity of diseases has in memorization and transmission of information about their treatments. We collected data from a rural population in Brazil during two different periods separated by eight years and compared the periods for changes according to the knowledge on treatments with drugs in the biomedical system and according to the incidence and severity of the diseases. We found 147 medicinal plants belonging to 58 botanical families. Our results show that biomedical and local systems complement each other and change over time for the cure of recurrent, instead of the most severe, events. We suggest that based on cultural biases, biomedical and local knowledge can coexist by complementing each other with regards to the range of resources used for healthcare, and that disease perception can guide the evolutionary path of medical systems. Our findings can help elucidate new biases that guide the evolution of medical systems and reinforce important issues in the healthcare literature.

ABSTRACT This study aimed to evaluate knowledge about and the usage and importance of aquatic vascular plants (AVPs) in the production of handicrafts by communities on the north coast of the state of Rio Grande do Sul in southern Brazil. The snowball technique was employed to locate people who use and have knowledge regarding the use of AVPs for handicrafts. Data were collected through semi-structured interviews and guided tours with 35 interviewees who were involved in artisanal activity at the time of the study. The data were analyzed using the importance value (IV) index and the consensus value for the forms of use (CMU). The Spearman correlation test (rs) was employed to determine the correlations of each social variable with the knowledge variables, and Mann-Whitney U tests to verify whether men and women exhibited differences in knowledge. The interviewees cited 16 AVPs that were employed in 17 types of handicrafts, among which the four main species were Schoenoplectus californicus, Typha domingensis, T. latifolia and Androtrichum giganteum. Interviewee age, residence time on site and time working with handicrafts were the main social parameters that described the level of knowledge and use of AVPs. These AVPs reflect cultural knowledge and complement family incomes.

ABSTRACT We investigated, through a temporal comparison, the extraction of non-timber forest resources by quantitatively analyzing the Conservation Priority Index (CPI). The study focused on the Fulni-ô Indigenous Territory, in the municipality of Águas Belas, PE (Northeast Brazil), which is characterized by caatinga vegetation (seasonal dry forest). Information on the availability of the exploited resources and the reported use of the species were obtained from vegetation sampling and semi-structured interviews, respectively. Our results demonstrated a reduction in species richness overtime, which may be due to continued resource extraction in the area, and that some species with low densities were even more affected. The species reported as being at high risk in the current study apparently did not differ from their status in the previous study, which supports the idea that these species are most evident in this situation more for their high potential of use than for their high densities. When we associate these events together with the disappearance of some rare species, we can conclude that the CPI was not efficient in predicting changes, and that the combination of variables used with the biological variables of the species needs to be adjusted.

Medicinal plants are an important aspect of local medical systems. The composition of a medicinal plant collection is influenced by cultural and environmental factors. Additionally, the functionality of a local medical system can be threatened by the replacement of native species with exotic ones, as well as by cultural factors such as the erosion of knowledge. The objectives of this study are: 1) examine the composition of the medicinal plant collection of two rural communities settled in the caatinga (savanna-like vegetation) of the state of Pernambuco (Brazil); 2) observe the role of exotic plants in the local medical systems; and 3) identify the profile of the species utilized according to the Utilitarian Redundancy Model. Similarities were observed between the medicinal floras of the communities studied, emphasizing the importance of the surrounding biome within the possibilities of species selection, although exotic species appear to contribute by increasing the diversity of species considered in the communities to be medicinal. The native species act broadly among the body systems recognized in the two communities, whereas exotic species act in specific body systems, for which there are few associated native species.