James Prosek tracks the life journey of Eli the Anguilla eel as she travels her mysterious "backward" migration from the sea to fresh water and back again. [4:39]

Article discusses Paleoindian migration and animal extinction at the end of the Pleistocene era and explores what we can learn about conservation given what we know about Pleistocene climate and extinction.

Brief overview of the caribou and an accompanying photo illustrate the physical adaptations that allow this animal to migrate to find its food supply.