Ka. Hanley et al., COMPARATIVE ECOLOGY OF SEXUAL AND ASEXUAL GECKO SPECIES (LEPIDODACTYLUS) IN FRENCH-POLYNESIA, Evolutionary ecology, 8(4), 1994, pp. 438-454
The asexual gecko Lepidodactylus lugubris, its sexual congener L. sp.
(Takapoto) and hybrids between the two species inhabit the atoll of Ta
kapoto, providing a natural experiment for studying co-existence and i
nteractions between asexual and sexual populations. The range of the s
exual species is confined to one section of the lagoon beach and the t
rees and buildings which abut it, whereas the asexual is distributed a
cross the whole atoll and occupies many habitats. Behavioural experime
nts revealed no asymmetry in levels of aggression between the two spec
ies, suggesting that the confinement of L. sp. (Takapoto) to the lagoo
n beach is not due to agonistic interactions. Ecological differences a
mong the constituent clones of the asexual species exist but cannot co
mpletely account for the broader habitat use of the asexual. Within a
single habitat, one clone of L. lugubris consumes a wider range of pre
y items than its sexual relative. Other studies have found that the as
exuals are extremely heterozygous relative to the sexuals; we hypothes
ize that their broad ecological tolerance may be attributable to heter
osis. The co-existence of the sexual and parthenogenetic lizards on th
is small island seems to be stable and may be facilitated by the speci
alization of the sexual taxon to beach habitats.