Beavers' orange teeth contain iron in their enamel, which makes their incisors tougher and more resistant to wear than human teeth enamel.

International Beaver Day, celebrated on April 7, recognizes a hardworking little engineer quietly building a better world—one stick at a time. The beaver—buck-toothed, paddle-tailed, and famously industrious—has been reshaping freshwater landscapes for millions of years. With their iron-reinforced orange incisors, these skilled rodents cut down trees and build dams that slow the flow of water, improve its quality, and create wetlands that support a remarkable diversity of life. Their sturdy lodges, made of branches and mud, have underwater entrances that protect them from predators and keep their families safe.

Among the world's largest rodents, beavers can reach nearly 3 feet in body length (excluding the tail). They are superbly adapted to aquatic life and can remain submerged for up to 15 minutes. Once heavily hunted and often misunderstood, they're now widely recognized as ecological powerhouses. Wherever they settle, these natural architects leave thriving habitats in their wake—proof that even small builders can shape big ecosystems.