Imagine trying to survive in rivers, streams and ponds in North America and Europe. For many animals, a habitat like this would be impossible. Yet the beaver, a mammal about 1 meter long, including its tail, thrives there, thanks to features that scientists call adaptations: traits that help a living thing survive in its environment.
Consider large orange front teeth that never stop growing: this adaptation let it chew through tree trunks. Equally important is a flat, paddle-shaped tail, which helps it steer in the water and slap a warning when danger is near. Without these traits, the beaver would struggle to last a single season.
As a herbivore, the beaver is an animal that eats only plants; it depends on tree bark, twigs and water plants. Its behavior matters as much as its body: it builds dams of sticks and mud that turn streams into ponds. Behaviors like this are adaptations too, even though you cannot see them in a photograph.
The next generation faces the same challenges. Young beavers, called kits, depend on their surroundings and on adult care. Kits can swim within a day of being born but stay with their family for about two years.
Perhaps most remarkable of all: the ponds beavers create become homes for fish, frogs, ducks and many other animals. Facts like this remind us that every animal's body tells a story about the place it lives.