Genetic consequences of an artificial introduction of guppies (Poecilia reticulata) in N. Trinidad

Abstract

The population genetic consequences of intraspecific introductions are not well understood. In the present study we verify the success of a 34-year-old transplantation of guppies, Poecilia reticulata , in Trinidad, and document the spread of the introduced fish. Gene frequencies in the introduced population are in accord with the stochastic effects of a founder event. Gene frequencies downstream of the transplant site suggest that the introduced fish have replaced the native guppy population throughout a substantial stretch of the river. There is strong evidence that the enzyme loci studied here are selectively neutral in the face of selection pressures known to have modified behaviour since the introduction.