Pale-throated sloth perched in a tree on Sloth Island, near Bartica on the Essequibo River, Guyana (© Suzi Eszterhas/Minden Pictures)

Coffee cherries in Quindío, Colombia (© The Colombian Way Ltda/Getty Images)

Manchots Adélie sur l'île de la Possession, Archipel Crozet, Antarctique (© Tui De Roy/Minden Pictures)

Adélie penguins at Possession Island, Antarctica (© Tui De Roy/Minden Pictures)

Sequence of enhanced-color images of Jupiter (© Enhanced image by Gerald Eichstädt and Seán Doran, CC BY-NC-SA, based on images provided courtesy of NASA/JPL-Caltech/SwRI/MSSS)

Aerial view of Marlborough Sounds, New Zealand (© Mathias Ortmann/Getty Images)

Aerial view of Marlborough Sounds, New Zealand (© Mathias Ortmann/Getty Images)

Cleveland Clinic Lou Ruvo Center for Brain Health in Las Vegas, Nevada (© Garry Belinsky/Offset)

Octopus spotted during a night dive near Kona, Hawaii (© Jeff Milisen/Alamy)

Letchworth State Park, New York (© Jay O'Brien/Danita Delimont)

Bubble Nebula (NGC 7635) (© NASA, ESA, and the Hubble Heritage Team STScI/AURA)

Arches National Park, Moab, Utah (© Whit Richardson/Alamy Stock Photo)

Boats massing for the Barcolana regatta in the Gulf of Trieste, Italy (© Ababsolutum/E+/Getty Images)

Highbush blueberry plants in Acadia National Park, Maine (© Danita Delimont/Gallo Images/Getty Images Plus)

Sunrise in Alberta, Canada (© Ambre Haller/Moment/Getty Images)

Close-up of a dragonfly wing (© Azwar Thaufeeq/500px/Getty Images)

A fossilized carboniferous fern (© Juan Carlos Munoz/Minden Pictures)

Autumn leaves and goldfish in Tokyo, Japan (© qrsk/Moment/Getty Images)

Chimney Rock and Uncompahgre National Forest, Colorado (© Cory Marshall/Tandem Stills + Motion)

Aerial view of a pumpkin patch in Half Moon Bay, California (© Tinker Street/Michael O'Neal/Gallery Stock)

Solomon R. Guggenheim Museum in New York City, 1959 (© AP Photo/Harry Harris)

Blackbird eating a crab apple in a garden in Wiltshire, United Kingdom (© Nick Upton/Minden Pictures)

County Bridge in New Hampshire, USA (© Denis Tangney Jr/E+/Getty Images)

Hancock-Greenfield Bridge (aka County Bridge) in New Hampshire (© Denis Tangney Jr/E+/Getty Images)

Ring-tailed lemurs in Madagascar for World Lemur Day (© Image Source/Alamy)

｢ディワリのランプ｣インド, グワーハーティー (© Anuwar Hazarika/Reuters)

Devotees light oil lamps on the banks of the Sarayu River in Ayodhya, India (© Rajesh Kumar Singh/AP Photo)

Fort Rock Valley Historical Homestead Museum, Oregon (© Prisma by Dukas Presseagentur GmbH/Alamy)

Straw-colored fruit bats in Kasanka National Park, Zambia (© Nick Garbutt/Minden Pictures)

Charles Bridge over the Vltava River in Prague, Czech Republic (© Martin Moxter/Offset)

一只坐在白杨树上的大雕鸮，阿尔伯塔 (© Ambre Haller/Getty Images)