Extras
On Costa Rica’s Pacific coast, turtles and jaguars collide in unexpected ways.
Uncover the secret world of New York and London’s resilient pigeon flocks.
Who rules the streets -- and skies -- of the city?
Times Square never shuts down, and neither do its pigeons.
Discover how pigeons find a mate for life.
Follow a female mountain lion in the Montana mountains over the course of a decade.
Mountain lions risk everything to hunt elk, prey more than twice their size.
A mother mountain lion risks her life to feed her six kittens.
It was once believed that walruses dug for clams with their tusks, but the truth is even stranger.