"Trees are better off if they produce large nuts. This is revealed in research by Patrick Jansen from Wageningen University. Scatterhoarding rodents appear to prefer burying larger nuts for later. The bigger the nut, the further it is buried from the tree and the more frequently it is forgotten.
Biologist Patrick Jansen investigated what happened to nuts as soon as they fell on the ground of the rainforest in French Guyana. He placed thousands of nuts on the ground in the forest. Each nut was marked with a fluorescent thread. Using video cameras he observed which animals removed the nuts. He then traced the nuts using the threads sticking out of the ground and followed them until they were either eaten or grew into a seedling.
He found that the vast majority of nuts were taken by acouchies, large guinea-pig-like rodents. Each nut is buried separately at a different location in the forest soil.
The rodents were found to be fussy. Larger nuts have a far greater chance of being successfully dispersed than smaller ones, as they are buried more frequently and further away. The rodents often forget such nuts and therefore these can successfully germinate. "
*Netherlands Organization for Scientific Research *