Impact of Colonization of an Invasive Species on Genetic Differentiation in New Environments:A Study on American Artemia franciscana (Crustacea:Anostraca) in the United Arab Emirates

摘要

Artemia franciscana,native to America,has recently colonized as non-indigenous population in Asia,Europe,North Africa,and Australia.We evaluated the effects of the colonization of A.franciscana on genetic differentiation in new environments in the United Arab Emirates(UAE).We used the COI marker to determine the genetic structure and origins of exotic populations in the UAE.Results confirmed the colonization of A.franciscana in two localities.Invasive populations of A.franciscana had significantly lower genetic variation than native populations in the Great Salt Lake and San Francisco Bay.Results showed that the studied populations could not have colonized directly from natural American habitats,and they possibly were from secondary introduction events of other non-indigenous populations.Genetic analysis yielded different demographic patterns for the studied invasive populations.The population in Al Wathba Wetland Reserve(AWWR)demonstrated demographic expansion,whereas in Godolphin Lakes(GL),it reached a demographic equilibrium.Neutrality tests showed an excess of recent and historical mutations in the COI gene pool of invasive AWWR Artemia in the new environment.The results suggest that different ecological conditions in new environments can exert selective pressures during the introduction of an exotic population,which can affect genetic variation.