The study by Hans ter Steege et al. investigates the tree flora of the Amazonian lowlands, focusing on the patterns of commonness, rarity, and richness of tree species. The researchers compiled and standardized species-level data from 1170 plots covering all major lowland forest types in the Amazon Basin and Guiana Shield (Amazonia). They estimated that the Amazonian lowlands harbor approximately 3.9 × 10^11 trees and around 16,000 tree species. The analysis revealed that just 227 "hyperdominant" species (representing 1.4% of the total) account for half of all trees in the region, while the rarest 11,000 species make up only 0.12% of the total. Most hyperdominants are habitat specialists and are dominant in one or two regions or forest types. The findings suggest that a small group of species, less diverse than the North American tree flora, dominates the world's most diverse tree community. The study also discusses the potential causes of hyperdominance, including competitive superiority and pre-1492 human cultivation, and highlights the importance of understanding these patterns for research in Amazonian biogeochemistry, ecology, and vegetation mapping.The study by Hans ter Steege et al. investigates the tree flora of the Amazonian lowlands, focusing on the patterns of commonness, rarity, and richness of tree species. The researchers compiled and standardized species-level data from 1170 plots covering all major lowland forest types in the Amazon Basin and Guiana Shield (Amazonia). They estimated that the Amazonian lowlands harbor approximately 3.9 × 10^11 trees and around 16,000 tree species. The analysis revealed that just 227 "hyperdominant" species (representing 1.4% of the total) account for half of all trees in the region, while the rarest 11,000 species make up only 0.12% of the total. Most hyperdominants are habitat specialists and are dominant in one or two regions or forest types. The findings suggest that a small group of species, less diverse than the North American tree flora, dominates the world's most diverse tree community. The study also discusses the potential causes of hyperdominance, including competitive superiority and pre-1492 human cultivation, and highlights the importance of understanding these patterns for research in Amazonian biogeochemistry, ecology, and vegetation mapping.