Birds serve as spreading agents: Unlike mammals, they lack the receptor which causes chile peppers to "burn" but are (equally) attracted to shiny red berries. And those make it a bit easier, again, being presented above the foliage and separating from their pedicels easily.

Having been eaten by birds, the seeds do not get digested but only receive a treatment which is good for breaking their dormancy, and are then deposited below other nurse trees, wrapped in their own personal starter package of fertilizer...