The shortspine thornyhead (Sebastolobus alascanus) is a species of fish in the Sebastidae family. It is sometimes referred to as the "idiot fish" or "idiot cod" due to its large oversize head/eyes. It is found in Canada, Russia, and the United States. Adult S. alascanus live predominantly in the oxygen minimum zone (OMZ), and thus require specific adaptations/exaptations in order to overcome the problems posed by the extremely low levels of oxygen saturation.