Plentuton

The plentuton split off from its ancestor. Since there weren't many predators to worry about, the plentuton became significantly larger the the plentutu, the plentuton has even lost its ability to fly, it has also developed a buoyant oil covered flesh, which acts as blubber to keep it warm when it dives deep into the lake. It has also adapted by modifying its tail into a fish-like shape, which allows it to swim faster. Its eyes have also moved to the top of its head. Its wing-leaves have become larger. The back legs have vanished while the front legs are still used to stay with its mother.