In the Yukon, Porcupine caribou travel 3,000 miles. This is the longest migration by land of any mammal on Earth. Monarch butterflies fly about 3,000 miles each year. Some will travel all the way ...

Monarch butterflies are important culturally and ecologically across North America. Generations have watched in wonder as yellow-and-black striped caterpillars fold into green-and-gold chrysalises and ...

A monarch butterfly feeds at Cape May Point State Park in Lower Township, N.J., Wednesday, Oct. 14, 2020.Get Photo Monarch butterflies roost as the sun begins to set at The Nature Conservancy's ...

and is seen in species as varied as monarch butterflies, caribou, and baleen whales. The main source of energy used for migration is fat. Fat stores about 8–10 times more energy than the ...