Damming a river can cause a lake to form.
Beavers know how to cut wood and build dams.
Beavers can create lakes.
How do beavers change waterways?
* They warm up the water
* marshes, bogs, and swamps
* They soil the water
* Earth's axis of rotation is tilted
* several different ways
* They make structures that split the water
* Genetic diversity is increased
* By tearing down dams