Barrier reef off the island of Grande Terre in the French overseas territory of New Caledonia (© Karsten Wrobel/Getty Images)

Knuthöjdsmossen, a nature reserve in Sweden (© Sven Halling/DEEPOL/plainpicture)

Little Pigeon River, Great Smoky Mountains National Park, Tennessee (© GreenStock/Getty Images)

Miravet on the Ebro River, Tarragona, Catalonia, Spain (© Eloi_Omella/Getty Images)

Sea otter floating in a kelp bed in Alaska Maritime National Wildlife Refuge (© Gerry Ellis/Minden Pictures)

Mona Vale Rockpool, Sydney, Australia (© jamenpercy/Getty Images)

Arlington National Cemetery in Virginia (© Dennis Govoni/Getty Images)

Butchart Gardens in Brentwood Bay, British Columbia, Canada (© 2009fotofriends/Shutterstock)

Jotunheimen National Park in Norway (© Marisa Estivill/Shutterstock)

A Julia butterfly on the nose of a yellow-spotted river turtle, Amazon Region, Ecuador (© Westend61/Getty Images)