In the Brazilian Pantanal, fish have a lot to say when spreading the seeds of tropical plants. Scientists have found that fish eat plant seeds and release and spread them after digestion. This process coincides with rainy times.
In times of rain in tropical forests, swamp waters rise. Thus, the fish that live in them also reach places previously inaccessible. At the same time, coinciding with the rainy season, trees and plants release seeds that reach the marshes. When fish eat and defecate they disperse. Thus, the seeds are deposited at the bottom of the marsh. After the rainy season, when the waters recede, from these seeds the plants are born and the forest expands. Considering that fish also perform this function, scientists believe that uncontrolled fishing in the area can affect the ecosystem of tropical forests.