This paper presents a critic review of the available knowledge on canopy gap structure and regeneration in Tropical Rain Forests. Separated on different issues such as gap size, type of treefall, physical environment, regeneration sources and ecological groups, each issue is explored in detail through the main studies published. Hence, old issues are discussed and gaps of knowledge are pointed out to enhance and ground future researches. As a result, it was observed that despite of more then three decades of research and several studies involving gap structure and regeneration, the research regarding the theme still has many questions to be answered. It also has limitations linked to the existing plurality of methods and to the difficulty of comparing different forests worldwide. It was concluded that the research involving gap structure and regeneration is on a theoretical refinement phase and, therefore, it is hard to evaluate the real contribution of canopy openings to the understanding of the different forests formations dynamics.
ecological groups; gap colonization; gap regeneration; tropical rain forest
