Fig trees and their specific pollinators have an obligate mutualistic relationship where both depend on each other to complete their life cycles. Each fig species is pollinated by one or more specific pollinators with host specificity maintained by physical and chemical barriers. Many mistakes however, have been recorded where pollinators enter atypical hosts and manage to pollinate them and produce hybrids. This thesis focuses on the fitness of experimentally generated hybrid fig trees and the ability of fig wasps to reproduce inside these hybrids. The dioecious fig tree F. montana and its pollinator Kradibia tentacularis from Indonesia and F. asperifolia from Uganda and their hybrids were used. Styles of female flowers in male and female figs lengthened at similar times during development and style lengths from female figs were always longer. In receptive phase figs, the ovipositor of K. tentacularis was able to reach all styles in male figs and some styles from female figs of hybrids and their parents. Using a new technique for staining fig wasps eggs, K. tentacularis was shown to lay one or two eggs in F. asperifolia, FI and backcross male figs, but failed to reproduce in F. asperifolia and FI s. In backcrosses, it could reproduce in figs of a few plants but not in the rest. It was inability to gall rather than inability to oviposit that prevented pollinator reproduction. FI seeds germinated and these seedlings grew as well as their parents, but later on most FIs died or were dwarfed. Backcrosses and other hybrid crosses showed better performance than FIs. Male FI s were sterile and hybrid fitness was lower than that of their parents, but FI female plants were able to produce fertile seeds when pollinated by F. montana, so introgression was possible.