The female wasp lays its eggs in to the flowers of the fig. Flowers that contain the eggs of the wasp do not produce seed but form gall like structures which protect the eggs and embryo of the wasp before hatching. Each egg laid costs the tree one seed, but the tree cannot be pollinated to produce seed without the wasp Pleistodontes imperialis. Once the eggs hatch from the galls they travel the syconium searching for female wasps to breed with, they then rip in to the galls and breed with the female wasps before they hatch. After they do this the male wasps then dig a hole in the side of the fig for the female wasps to escape, this is the male wasps only purpose, he does not ever leave the fig. The female wasp before leaving the fig after hatching then collects pollen from the male flowers then proceeds to leave the fig via the tunnel provided by the male wasp in search of another fig tree (ficus rubiginosa) to start the process all over again. .
What we wanted to find out is what keeps this mutualism stable and why doesn't one partner in the mutualism exploit the other causing the mutualism to eventually collapse. And is seed set influenced by parasatoid numbers in the population. Also, what stops the wasp using up all of the ovules and therefore restricting the fig producing little or no seed. The answer to this question may be the presence of the parasatoid wasps in this mutualism; Parasatoid wasps are wasps that attack pollinators from outside the fruit, (Dunn et al., 2008). The parasatoid wasps have a long ovipositor which they drill down through the skin of the fig to find the pollinator wasp Pleistodontes imperialis they then lay their eggs in the wasp and when they hatch they feed on the pollinating wasp. .
Therefore a greater presence of parasatoid wasps helps keep down the numbers of the pollinating wasp stabilizing the mutualism between the fig wasp and fig tree (ficus rubiginosa).