A genetic bottleneck in populations of a New Zealand endemic ant associated with density of an invasive predatory wasp

作者：Burne A R^*; Ritchie P A; Gruber M A M; Lester P J

来源：Insectes Sociaux, 2017, 64(1): 65-74.

DOI：10.1007/s00040-016-0512-0

• Genetic bottleneck
• Invasive predator
• Prolasius advenus
• Vespula vulgaris

Predation by invasive species can reduce the effective population size of native species, which may cause increased levels of genetic drift resulting in a loss of genetic diversity. The magnitude of these effects appears likely to be related to invader abundance. In the Fuscospora beech forests of New Zealand, dispersal of the most abundant ant species, Prolasius advenus (Fr.Smith) (Hymenoptera: Formicidae), coincides with the peak abundance of the invasive predatory wasp Vespula vulgaris (L.) (Hymenoptera: Vespidae). Dispersing winged ant queens can comprise more than 25 % of the wasps' diet. We hypothesised that the predation of wasps on queen ants could increase genetic drift on ant populations when wasps were at high density, which would erode genetic diversity and potentially fitness. We used six microsatellite markers to examine genetic diversity, population genetic structure and to test for evidence of a genetic bottleneck in P. advenus populations from seven sites with varying levels of wasp infestation. Populations of ants at high wasp densities showed evidence of a genetic bottleneck, which we suggest is the result of intense predation on dispersing queens by Vespula wasps. The seven sites examined were broadly divided into two distinct populations with some evidence of either limited admixture or derivation from a common ancestral population. Our results are consistent with a short term effect of high levels of predation by an invasive species with long-term implications for the recipient species.

• 出版日期2017-2