How Andean Plants In The Moist Forests Of The Brazilian Atlantic Coast Got There

The presence of Andean plant genera in the moist forests of the Brazilian Atlantic Coast has been historically hypothesized as the result of cross-continental migrations starting at the eastern Andean flanks. This paper tests hypotheses of former connections between the Atlantic and Andean forests by examining distribution patterns of selected cool and moist-adapted plant arboreal taxa present in 54 South American pollen records of the Last Glacial Maximum (LGM), about 19,000–23,000 calibrated years before present, known to occur in both plant domains. The researchers explored connectivity patterns between these two neotropical regions as well as individual ecological niches during the LGM by way of cluster analysis of fossil assemblages and modern plant distributions. Additionally, the team examined the ecological niche of 137 plant species with shared distributions between the Andes and coastal Brazil. The results revealed five complex connectivity patterns for South American vegetation linking Andean, Amazonian and Atlantic Forests and one disjunct distribution in southern Chile. This study also provides a better understanding of vegetation cover on the large and shallow South American continental shelf that was exposed due to a global sea level drop.
February 9. 2024