| Southwestern Deserts, Reptiles |
Their venom isn't injected through hollow fangs like a snake, but instead flows up through grooves in their teeth as they chew. |
| Continent-wide, Canines |
Fierce eradication efforts have actually caused this resilient canine's population to explode and expand geographically. |
| Northern Hemisphere, Apex Predators |
Despite their terrifying cinematic reputation as apex carnivores, these massive titans are actually largely vegetarian. |
| Arctic Coasts, Marine Mammals |
Beneath their iconic fluffy white coats, these maritime predators actually have jet-black skin to absorb every ounce of solar heat. |
| Eastern & Central Woodlands, Rodents |
Far beyond their fame as winter weather forecasters, they are prodigious subterranean architects capable of moving thousands of pounds of dirt. |
| Western Deserts, Rodents |
These highly specialized jumpers can survive their entire lives without ever drinking a single drop of liquid water. |
| Southern US & Americas, Mammals |
The nine-banded armadillo routinely gives birth to exactly four genetically identical offspring every single time. |
| Florida & Gulf Coast, Marine Mammals |
These slow-moving, aquatic 'sea cows' are actually the closest living evolutionary relatives of the elephant. |
| Great Plains, Hoofed Mammals |
Despite weighing up to 2,000 pounds, these massive herbivores are surprisingly agile and can run at speeds up to 35 miles per hour. |
| Southeastern Wetlands, Reptiles |
During freezing winter snaps, they survive by letting themselves freeze into the ice with just their snouts poking out to breathe. |
| Continental Flight Paths, Insects |
Their famous migration from Canada to Mexico is a multi-generational relay race where no single butterfly makes the complete round trip. |
| Atlantic Rivers & Coasts, Fish |
No one has ever observed American or European eels mating in the wild, so their spawning remains one of nature's biggest mysteries. |
| Rivers and wetlands across the continent |
The sound of running water makes them start building. |
| Western United States and Baja California |
By 1987 only 22 were left, and all were captured for a breeding programme. |
| Boreal forests of Canada, Alaska and the northern US |
Their antlers are the fastest-growing bone on Earth. |
| From Canada to Central America |
They wet their food to sharpen their sense of touch, not to clean it. |
| Grasslands and deserts of the American West |
Its closest living relatives are the giraffe and the okapi. |
| Rivers of the eastern and central United States |
It breathes mostly through its wrinkly skin. |
| Deserts and canyons of the Southwest |
Its hind feet rotate 180 degrees so it can climb down rocks headfirst. |
| Forests from Alaska to Mexico |
They cannot shoot their quills. |