Giant Pambu

The giant pambu evolved from the pink pambu. It's native to the Ittiz-Nuke Rainforest. It's much taller than its ancestor and evolved a thicker trunk. It grows in periods, and whenever one period is over, a cluster of leaves grows at the top of the new segment. The "wood", which is formed later in the period, is brighter than the older "wood". That's why each segment is dark at the bottom and bright at the top. Because of a struggle for light, the giant pambu never stops growing, and, after it reaches a certain height, it will just topple down and die.