Reproduction and maternal care increases oxidative stress in a mouthbrooding cichlid fish

Investment in reproduction and post-zygotic parental care is an energetically costly, yet fundamental aspect of the life history strategies in many species. Recently, oxidative stress has received attention as a potential mediator in the trade-off between reproduction, growth and survival. During activities that increase metabolic activity, such as providing offspring care, an overproduction of reactive oxygen species can occur that cannot be counteracted by antioxidants, leading to oxidative stress and tissue damage. Here, we investigated the oxidative costs of reproduction and maternal care over the course of the reproductive cycle in a mouthbrooding cichlid fish within socially stable and unstable environments. We manipulated social stability by disrupting the habitat in socially unstable tanks. We expected to see an increase in the burden of maternal care within unstable environments due to increased male harassment of females as a byproduct of increased male-male aggression. We fou...