Placing Main Topics, Subtopics, and Details in Outline Form

How does a beaver build a home? First it builds a dam. After locating a good spot for it, the beaver places sticks and stones in the streambed, carefully laying the large ends of the sticks upstream. Then the sticks are held together with mud. The beaver keeps making layers of sticks and mud until the dam is high enough to flood the area. Next it builds canals. The canals go from the dam to the area where the beaver gets the logs. Now it uses the canals to float sticks and logs. Also, the canals make travel safer. Finally, the beaver is ready to build a lodge. While building the dam, the beaver lives in a den on a bank. As the water rises, a beaver is forced to dig higher and higher. Soon it is above ground. Then it begins piling mud and sticks above to make the room even higher. When it is finished, the beaver can have a room two feet high and about four feet wide. It is formed from the mud and sticks above water. Walls are plastered with mud and are airtight. There is an air hole in the top. The lodge usually has two entrances. One goes almost straight up so the beaver can get wood through it for winter. Each beaver has a bed made of grass or tiny bits of chewed-up wood. The beavers' bodies give off enough heat to keep the lodge very warm.