The study examines the behavior and population genetics of the Argentine ant (Linepithema humile) in both its native and introduced ranges to understand the factors contributing to its success as an invasive species. The authors found that introduced populations of Argentine ants have undergone a genetic bottleneck, leading to reduced genetic diversity and a lack of intraspecific aggression. This reduction in genetic diversity allows for the formation of supercolonies, where workers and queens mix freely among physically separate nests, reducing territorial costs and increasing colony size. In contrast, native populations exhibit higher genetic variability and significant intraspecific aggression. The findings suggest that a genetic bottleneck can lead to ecological success, challenging the traditional view that reductions in genetic diversity are generally detrimental. The study also provides insights into the evolution of unicoloniality, a trait often seen as a challenge to kin selection theory. The results have implications for understanding the dynamics of invasive species and potential control strategies.The study examines the behavior and population genetics of the Argentine ant (Linepithema humile) in both its native and introduced ranges to understand the factors contributing to its success as an invasive species. The authors found that introduced populations of Argentine ants have undergone a genetic bottleneck, leading to reduced genetic diversity and a lack of intraspecific aggression. This reduction in genetic diversity allows for the formation of supercolonies, where workers and queens mix freely among physically separate nests, reducing territorial costs and increasing colony size. In contrast, native populations exhibit higher genetic variability and significant intraspecific aggression. The findings suggest that a genetic bottleneck can lead to ecological success, challenging the traditional view that reductions in genetic diversity are generally detrimental. The study also provides insights into the evolution of unicoloniality, a trait often seen as a challenge to kin selection theory. The results have implications for understanding the dynamics of invasive species and potential control strategies.