Ficus Maxima - Reproduction

Reproduction

Figs have an obligate mutualism with fig wasps (Agaonidae); figs are only pollinated by fig wasps, and fig wasps are only able to reproduce in fig flowers. Generally, each fig species depends on a single species of fig wasp for pollination, and each species of fig wasp can only reproduce in the flowers of a single species of fig tree. Ficus maxima is pollinated by Tetrapus americanus, although recent work suggests that the species known as T. americanus is a cryptic species complex of at least two species, which are not sister taxa.

Figs have complicated inflorescences called syconia. Flowers are entirely contained within an enclosed structure. Their only connection with the outside is through a small pore called ostiole. Monoecious figs like F. maxima have both male and female flowers within the syconium. Female flowers mature first. Once mature, they produce a volatile chemical attractant which is recognised by female wasps belonging to the species Tetrapus americanus. Female wasps of this species are about 2 mm (0.08 in) long and are capable of producing about 190 offspring.

Female fig wasps arrive carrying pollen from their natal tree and squeeze their way through the ostiole into the interior of the syconium. The syncomium bears 500–600 female flowers arranged in multiple layers - those that are closer to the outer wall of the fig have short pedicels and long styles, while those that are located closer to the interior of the chamber have long pedicels and short styles. Female wasps generally lay their eggs in the short-styled flowers, while longer-styled flowers were more likely to be pollinated. The eggs hatch and the larvae parasitise the flowers in which they were laid. Pollinated flowers which have not been parasitised give rise to seeds.

Male wasps mature and emerge before the females. They mate with the females, which have not yet emerged from their galls. Males cut exit holes in the outer wall of the syconium, through which the females exit the fig. The male flowers mature around the same time as the female wasps emerge and shed their pollen on the newly emerged females; like about one third of figs, F. maxima is passively pollinated. The newly emerged female wasps leave through the exit holes the males have cut and fly off to find a syconium in which to lay their eggs. The figs then ripen. The ripe figs are eaten by a variety of mammals and birds which disperse the seeds.