Fathead Swarmer

The fathead swarmer has split from its ancestor and developed a more "predatory" life style. Due to the little food within the Yannick ice caves, the ancestors of the fathead swarmer began to specialize on feeding upon the larva of other swarmers that began to evolve alongside it. To aid in this, it has developed a primitive proto-jaw that allows it to gulp in water and thus force food that would otherwise attempt to swim away. They have also evolved the tips of their fins into spines that allow them to walk along the bottom of the caves and thus conserve valuable energy. This, combined with their slow metabolism, allows them to go for long periods of time without much food.

Females are larger than males by at least 2 cm and become more fertile with age. They also have a larger fatty dome that, because of its appearance, earned them their name. The dome-like mass helps to distinguish between the sexes, as the males have an insignificantly sized one, as well as help to focus their sonar. Mating takes place during the beginning of the warmer months, during which the females will produce dozens of young who will be free to feast on the young and eggs of other swarmer species