Downed trees fill with insects and feed woodpeckers and sapsuckers. The increased wet area around the beaver pond absorbs flood waves and slowly infiltrates water into the groundwater table. When the building materials deplete, the beavers move on to another location. The dam, filled high with rich, black organic muck, breaks down, causing the water to change course and meander around. As the area dries it becomes a rich pasture of grasses, feeding herbivores which feed predators. The meadow, recolonized by the seeds of the trees that initiated the process, begins anew. Multiply this lifecycle by 13,000 years and you have the continual development of fertile valley bottomlands and a regenerative model for human developments."
-Rachel Olivieri, Alternet.org