The global latitudinal gradient of biodiversity represents the most conspicuous pattern of correlation between the environmental/geographic variation and biodiversity distribution. Yet, the relative roles of all ecological, geographic, and historical variables that can explain the gradient and how groups diversify throughout the gradient are unclear. Thus, we lack a connection between the macroevolutionary patterns and microevolutionary processes. The community assembly of ferns from the American continent was evaluated to identify the possible links between the latitudinal gradient of biodiversity and the processes of speciation and extinction. As expected, the fern community was found to be clearly following the gradient: the number of species and species abundance decrease with latitude; this pattern is associated to a strong phylogenetic structure. These results suggest that the fern community from the American continent follows the latitudinal gradient. Then, using linear regressions, some classical hypotheses that have been proposed to explain the latitudinal gradient were tested. However, none of the hypotheses give a fully satisfactory explanation. Rather, the data suggest that to increase diversity and maintain the gradient, the relative roles of environmental differentiation, geographic isolation, niche divergence, and time since divergence between sister species pairs vary with latitude. This research expects to provide a model that can allow conceiving speciation as global process.