2. Materials and methods
2.1. Experimental animals
Larval killifish (F. heteroclitus) were produced from an inhouse culture of wild caught specimens (St. Augustine, FL).
Adult killifish were maintained in flow-through SW at ambient temperature and were fed ad libitum commercially available
dry pellet food. Groups consisting of one male and three to four females were placed in separate tanks. For spawning, tanks were fittedwith egg laying substrates overnight. Egg laying substrates consisted of short (2 cm) lengths of PVC tubing covered with fine plastic mesh in the bottom and a wider plastic mesh on the top. Thewider plasticmesh on the top of the PVCtubing allowed for eggs to fall through and collect on the fine mesh in the bottom while preventing the adults from having access to the eggs. Each morning eggs were removed from the spawning tanks, rinsed briefly in de-ionizedwater andwere placed onmoist (FW)