“…We used a well-studied cognitive task-visual lateralization (Clayton, 1993;McGrew and Marchant, 1999;Pascual et al, 2004;Rogers et al, 2004;Vallortigara and Rogers, 2005;Rogers and Vallortigara, 2008). Visual lateralization is known to vary based on the stimulus (Bisazza et al, 1997a(Bisazza et al, ,b, 1998(Bisazza et al, , 1999De Santi et al, 2001;Sovrano et al, 2001;Fuss et al, 2019), environmental pressures such as predation (Brown et al, 2004;Ferrari et al, 2015), and density dependent selection (Ghirlanda and Vallortigara, 2004;Nakajima et al, 2004). Visual lateralization is present in many poeciliid species in response to some but not all stimuli, including the two species used in this study: Girardinus falcatus, Gambusia holbrooki, G. nicaraguensis, Brachyrhaphis roseni (Bisazza et al, 1997b), Poecilia latipinna, P. formosa, P. mexicana, P. reticulata (Fuss et al, 2019).…”