Arenal Volcano seen from Monteverde, Costa Rica (© Lukas Bischoff/Getty Images)

Butterflies in a meadow in Germany (© Albert Fertl/Getty Images)

Modica, Sicily, Italy (© Sandro Bisaro/Getty Images)

Leopard in a tree, Kruger National Park, South Africa (© Tonino De Marco/Minden Pictures)

Traffic circle and highway in Bangkok, Thailand (© Avigator Fortuner/Shutterstock)

Wahclella Falls in the Columbia River Gorge, Oregon (© Eric Vogt/Tandem Stills + Motion)

Roques de Benet, Els Ports Natural Park, Catalonia, Spain (© Sergi Boixader/Alamy)

Aerial view of Iguazú Falls, Foz do Iguaçu, Brazil (© Nido Huebl/Shutterstock)

Bisti/De-Na-Zin Wilderness Area, New Mexico (© Ian Shive/Tandem Stills + Motion)

Prosecco Hills of Conegliano and Valdobbiadene, Veneto, Italy (© Olimpio Fantuz/eStock Photo)

A koala sleeping in a eucalyptus tree, Australia (© Anton Rogozin/Getty Images)

Bryce Canyon National Park, Utah (© Jim Patterson/Tandem Stills + Motion)

Lesser flamingos flying over Lake Magadi, Kenya (© Vicki Jauron, Babylon and Beyond Photography/Getty Images)

Wat Phra Ngam, Ayutthaya Historical Park, Thailand (© boonchai wedmakawand/Alamy)

Anza-Borrego Desert State Park, California (© Stephen Matera/Tandem Stills + Motion)

Eurasian blue tit, United Kingdom (© Anne Coatesy/iStock/Getty Images)

St. Finian's Bay, County Kerry, Ireland (© Atlantide Phototravel/Getty Images)

Elephant Rock, Al-Ula, Saudi Arabia (© Lubo Ivanko/Shutterstock)

Tree frog on leaf (© Tetsuya Tanooka/DEEPOL by plainpicture)

Cave Dale and Peveril Castle in Castleton, Peak District National Park, Derbyshire, England (© James Osmond/Alamy)

Bwindi Impenetrable Forest, Uganda (© Art Wolfe/DanitaDelimont.com)

Blue Spring, Te Waihou Walkway, New Zealand (© Ian Beattie/Alamy)

Large anvil clouds above the Amazon in Brazil (© NASA)

Silvereyes on a cherry blossom branch, South Korea (© TigerSeo/Getty Images)

Tulip fields in Fraser Valley, Abbotsford, British Columbia, Canada (© LeonU/Getty Images)

Seawater cascades over an ancient coral reef, Hang Rai, Vietnam (© Thang Tat Nguyen/Getty Images)

Tea plantation near Munnar, Kerala, India (© Peter Zelei Images/Getty Images)

Cherry blossoms in Shanghai, China (© Yaorusheng/Getty Images)

South Stack Lighthouse at sunset, Holyhead, Wales, UK (© mariotlr/Getty Images)

Brown-throated three-toed sloth sleeping in cecropia tree, Costa Rica (© Juan Carlos Vindas/Getty Images)

Great egret in the Pantanal, Brazil (© Geraldi Corsi/Getty Images)