Epiphyte Loads, Tree Falls, and Perennial Forest Disruption: A Mechanism for Maintaining Higher Tree Species Richness in the Tropics Without Animals

A new hypothesis is given to account for the maintenance of higher tree species richness at lower latitudes, which does not invoke the influence of animals. Vine and epiphyte loads of wet, lowland forest canopy increase dramatically at low latitudes, and these loads may be an important cause of the high tree fall rates of such tropical forests. The perennial patchwork of disturbance generated by high tree fall rates could maintain forest as a perpetual preclimax mosaic, increasing the diversity of sapling environments, and reducing the frequency of long-term competitive interactions between adjacent individuals.