Andean bears are a keystone species, playing a major role in maintaining the dynamics of the cloud forest ecosystem they live in. The bears in the Intag region of Ecuador are known to rip the bark off Brunelia trees. This causes the premature death and fall of the trees, creating clearings in the forest, allowing light to get through to the undergrowth, which permits smaller trees to grow and therefore promotes new life in the forest. Andean bears are very agile and often climb trees in search of bromeliads and fruits. In doing this, and jumping from tree to tree, they may break branches which again allows light to pass down to the undergrowth, and so promotes new growth. By eating fruits of the forest, the bears disperse seeds to other parts of the forest in their faeces. This is another method by which the Andean bear promotes natural regeneration of the cloud forest ecosystem, which is vital as the "lungs" of the planet and to maintain the natural water cycle.
The mountain tapir is a keystone species of the high Andes. Because of a relatively inefficient digestive system, many plant seeds pass straight through the tapir's stomach and germinate in the dung of the tapir. This is assisted by the tendency of the tapir to defecate near water. Two plants in particular, the endangered wax palm and the highland lupine, almost disappear whenever the tapir is forced from an area.