'The Wall for Peace' and the Eiffel Tower in Paris for the International Day of Peace (© Prisma by Dukas Presseagentur GmbH/Alamy)

Red squirrel in heather, Scotland (© Christopher Drabble/Alamy)

石楠花丛中的一只欧亚红松鼠，英格兰 (© Christopher Drabble/Alamy)

'Vessel' at Hudson Yards in New York City (© Paparacy/Shutterstock)

Wimbachklamm, Ramsau, Bavaria, Germany (© Westend61 GmbH/Alamy)

Tegallalang terrace farms in Ubud, Bali, Indonesia (© gorgeoussab/Shutterstock)

武陵山脉的最高峰梵净山，中国西南 (© Keitma/Alamy)

Southern yellow-billed hornbills in Kruger National Park, South Africa (© Ben Cranke/Getty Image)

Southern yellow-billed hornbills in Kruger National Park, South Africa (© Ben Cranke/Getty Image)

Giraffengazelle im Tsavo-Nationalpark, Kenia (© Byrdyak/iStock/Getty Images Plus)

Aerial view of rainforest and Daintree River, Australia (© Peter Adams/Offset)

Poplar trees in New England, New South Wales, Australia (© ILYA GENKIN/Alamy)

The Milky Way seen from Canyonlands National Park in Utah (© Cavan Images/Offset)

Maple leaves in autumn (© Katsuaki Shoda/EyeEm/Getty Images)

The Pando quaking aspen in Fishlake National Forest, Utah (© Don Paulson/Danita Delimont)

Surfboards in a row (© plainpicture/Tony Arruza)

The road over Stoke Pero Common, Dunkery Hill, Exmoor, England (© David Noton/Alamy)

The Villarrica volcano in Chile on 2 September, 2018 (© Cristobal Saavedra Escobar/Reuters)

苏必利尔国家森林中一只常见的潜鸟，明尼苏达州 (© Jim Brandenburg/Minden Pictures)

A common loon in the Superior National Forest, Minnesota (© Jim Brandenburg/Minden Pictures)

鸟瞰生长在森林中的树木，加拿大不列颠哥伦比亚省温哥华 (© Michael Wu/EyeEm/Getty Images)

秋分时日的卡斯蒂略金字塔，墨西哥奇琴伊察 (© Somatuscani/Getty Images Plus)

一只正在树上吃东西的山地大猩猩，乌干达布恩迪国家公园 (© Robert Haasmann/Minden Pictures)

A mountain gorilla eating in a tree, Bwindi Impenetrable National Park, Uganda (© Robert Haasmann/Minden Pictures)

鱼湖国家森林中的美洲山杨，犹他州 (© Don Paulson/Danita Delimont)

德纳斯雷亚尔斯自然公园Castildetierra上空绚丽的日落，西班牙纳瓦拉 (© Inigofotografia/iStock/Getty Images Plus)

Colorful sunset over Castildetierra, in the Natural Park of Bardenas Reales, Navarre, Spain (© Inigofotografia/iStock/Getty Images Plus)

Blooming jacaranda trees in New Farm Park, Brisbane, Australia (© Walter Bibikow/Danita Delimont)

Autumnal landscape near the town of Clavijo in Spain's Rioja district (© Olimpio Fantuz/eStock Photo)

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