Beavers are amazing rodents.

They have long teeth that never stop growing; they control their length by gnawing on wood.

They have fat-insulated bodies, webbed feet, and a large flat tail—which make them clumsy and exposed on land but quick and graceful in the water.

Most importantly, beavers cut down trees to dam streams and rivers to make their homes. To many humans, these activities seem destructive.

But the ponds and wetlands they create are essential for hundreds of other species that have coevolved with beavers over the last 10 million years.

These include fish and insects, water birds, amphibians and reptiles, large grazing animals, and a multitude of plant species.

Beaver ponds and wetlands provide food, water and shelter for many of these species—and create huge benefits for the forest:

The ponds protect the woods from fires. Their surface water slowly drains into and recharges the water table. They filter out particulates to purify streams. They slow the progress of, and can even stop, floods. And serve as water repositories in times of drought.

A century ago, trappers had hunted beavers nearly to extinction, for their furs. But around 1900, laws were enacted to protect them, and their population has since rebounded.

Thankfully, beavers now occupy nearly all of their previous range, shaping and improving the landscape from Canada all the way down to northern Mexico.