We examined the hypothesis that pseudosexual behaviour facilitates reproduction in the unisexual gecko, Lepidodactylus luguhris. Thirty-eight hatchlings were housed in isolated or social conditions. Age at initial egg development, days between egg development and laying for the geckos’first three clutches of eggs, inter-clutch intervals and dominance behaviours were recorded. Lepidodactylus lugubris developed their first clutch of eggs at about 9·5 months of age after their endolymphatic sacs became externally visible. The geckos laid their eggs about 28–30 days later with smaller geckos requiring more time between egg development and laying than larger geckos. Grouped geckos formed dominance hierarchies. In the triad and quadrad groups, the subordinate geckos’growth rates were slowed and their fecundity was suppressed. Pseudosexual behaviour was not observed in the geckos and was unrelated to fecundity because isolated geckos developed and laid three clutches of eggs at the same rate as grouped geckos. Dominance behaviour, not pseudosexual behaviour, was related to fecundity in L. lugubris. Dominance behaviour may facilitate dispersal in this colonizing species because subordinate geckos could increase their fecundity by moving to less populated areas.