“…Of the killifish populations known to have adapted to environmental contaminants, several have adapted specifically to chemicals that act via AhR-dependent mechanisms, and alterations to the AhR pathway seem to be a critical component of the adaptation (Prince and Cooper, 1995a,b;Nacci et al, 1999;Powell et al, 2000;Bello et al, 2001;Ownby et al, 2002;Bacanskas et al, 2004;Hahn et al, 2004). Specifically, all of these populations exhibit a marked reduction in CYP1A inducibility in response to a variety of AhR agonists (Prince and Cooper, 1995a;Elskus et al, 1999;Nacci et al, 1999;Bello et al, 2001;Arzuaga and Elskus, 2002;Meyer et al, 2002.…”