+Our classification of colonization groups defies the traditional
+dichotomy between ‘late successional’ shade-tolerant and ‘early successional’
+pioneer species. Many tree species, classified here as
+regenerating pioneers on the basis of their population structure in
+secondary forests, are common in both young secondary forest and
+mature forests in this region (Guariguata et al. 1997), and many are
+important timber species (Vilchez et al. 2008). These generalists are
+by far the most abundant species of seedlings and saplings, conferring
+a high degree of resilience in the wet tropical forests of NE
+Costa Rica (Norden et al. 2009, Letcher & Chazdon 2009). The
+high abundance of regenerating pioneers in seedling and sapling
+size classes clearly shows that species with shade-tolerant seedlings
+can also recruit as trees early in succession. For these species, early
+tree colonization enhances seedling and sapling recruitment during
+the first 20–30 yr of succession, due to local seed rain. Species
+abundance and size distribution depend strongly on chance colonization
+events early in succession (Chazdon 2008). Other studies
+have shown that mature forest species are able to colonize early in
+succession (Finegan 1996, van Breugel et al. 2007, Franklin & Rey
+2007, Ochoa-Gaona et al. 2007), emphasizing the importance of
+initial floristic composition in the determination of successional
+pathways and rates of forest regrowth. On the other hand, significant
+numbers of species in our sites (40% overall and the majority
+of rare species) colonized only after canopy closure, and these species
+may not occur as mature individuals until decades after agricultural
+abandonment.
+
+