Temporal Genetic Variation in a Population of Aphanius fasciatus (Cyprinodontidae) from a Brackish-water Habitat at Elba Island (Italy) |
| |
Authors: | Ferruccio Maltagliati Laura Camilli |
| |
Institution: | (1) Dipartimento di Zoologia e Antropologia Biologica, Corso Margherita di Savoia, 15, I-07100 Sassari, Italy;(2) Dipartimento di Scienze dell'Uomo e dell'Ambiente, Via A. Volta, 6, I-56126 Pisa, Italy |
| |
Abstract: | Allozyme electrophoresis was used to assess temporal genetic variation in three successive generations of the Mediterranean killifish, Aphanius fasciatus. Samplings were carried out in 1995, 1996 and 1997 in a brackish-water habitat at Elba Island, Italy and a total of 212 specimens were collected. The five loci for which polymorphism has been detected in a previous study were assayed. Mean expected heterozygosity values H=0.397 (SE 0.077), H=0.336 (SE 0.092) and H=0.313 (SE 0.092) in 1995, 1996 and 1997, respectively] were not significantly different by ANOVA test. Deviations from Hardy–Weinberg equilibrium were minimal, with only one out of the 15 probability tests showing a significant departure from the equilibrium; whereas genotypic linkage disequilibrium was not detected. Values of Nei's genetic distance were lower than 0.04. Temporal genetic variation in the A. fasciatus population at Elba Island was observed, with F-statistics indicating significant genetic divergence among samples ( =0.035, SE 0.027, p<0.001). Genetic drift acting on two loci (GPD-1
* and LDH-3
*) is presumably the main force determining the temporal genetic heterogeneity observed; however, the occurrence of selection on individual loci and/or sampling error cannot be excluded. The observed allelic variation among generations in a single population of A. fasciatus is much less than levels observed among geographically discrete samples in previous studies. |
| |
Keywords: | conservation allozymes generations genetic distance genetic drift selection |
本文献已被 SpringerLink 等数据库收录! |
|