Young child with its mother in Burkina Faso, formerly Upper Volta, Africa.

Two blue wildebeest (Connochaetes taurinus) go down a steep, dirt riverbank gulley while others stand watching on the edge, Serengeti National Park, Tanzania, Africa

Men swimming in the icy glacial lakes of Mount Cook National Park; Canterbury, New Zealand

Men swimming in the icy glacial lakes of Mount Cook National Park; Canterbury, New Zealand

Viewpoint, looking down at feet standing next to foamy surf on Kamaole Beach at the water's edge, Kihei, Maui, Hawaii, United States of America

Girls in a row at edge of swimming pool

Girl standing at edge of swimming pool with inflatable ring