Moluscos límnicos do novo mundo: padrões de distribuição e implicações no ensino de biogeografia

Abstract

The establishment of bioregions is essential in understanding biodiversity variation patterns. Gastropods and bivalves own a broad distribution in freshwater ecosystems, mostly affected by human interference. Here, we aimed to determine the New World regionalization with freshwater mollusks occurrence data, as well as to investigate the efficacy of 'Ecologia I' in basic Biogeography concepts learning for biology licensure students in Instituto Federal do Piauí - Campus Uruçuí (IFPI - Uruçuí). We conducted a network analysis based on a dataset of 1,147 species, using the Infomap Bioregions algorithm. We calculated the richness and weighted endemism per grid cell. Besides, we collect the perceptions of biology licensure students in IFPI - Uruçuí. Then, we present ten assertions to two different student groups: that attended and not attended 'Ecologia I'. The hit score was compared using the t-test. The richest grid cells were placed in the southeast USA. Alabama, Florida, and Georgia are states with high endemism levels. A list of eight bioregions was reported in New World. Mississippi - Canadian was the richest bioregion (652 spp), followed by Florida Peninsula (399 spp), Tennessee (398 spp), and Atlantic (305 spp). South American bioregion comprises a high percentage of endemic species (80.5%). Our results highlight Mississippi - Canadian, South American, Pacific, Central America Province bioregions as great potential for targeted conservation. No significant differences in hit scores between student groups were reported (t = -1.58; p = 0.12). Thus, 'Ecologia I' had no influence on the basics biogeography concepts learning. Although some students show little interest in Biogeography and Ecology, both groups believe that Biogeography should be included in the formal curriculum. Our results provide insights into biogeographical schemes of freshwater mollusks, as well as the importance of better application of biogeography concepts in Ecologia I' or other disciplines in IFPI - Uruçuí