Passengers wait at the departure hall of the Beijing Railway Station in central Beijing, China January 27, 2017 as China gears up for Lunar New Year, when hundreds of millions of people head home. (Photo by Damir Sagolj/Reuters)

In 2013, the United Nations General Assembly officially designated November 19 as World Toilet Day, which is coordinated by UN-Water in collaboration with governments and partners. Here: An open-air toilet and a hot spring shower are seen in the middle of nowhere on the road to the Krafla geothermal power station and lava fields, near Reykjahlid and Lake Myvatn in northeastern Iceland, on August 19, 2012. (Photo by Mariana Suarez/AFP Photo)

National Geographic has created “Air, Land & Sea: the 50 greatest wildlife photographs” exhibition. Here: CT4 Crocodile cave on the Salamat river. Set up with Nathan Williamson last chip rain came while we were with the nomads. (Photo by Michael Nichols/National Geographic)

Migrant workers hang on to a door of a moving bus as they return to their villages after Delhi government ordered a six-day lockdown to limit the spread of the coronavirus disease (COVID-19), in Ghaziabad on the outskirts of New Delhi, India, April 20, 2021. (Photo by Adnan Abidi/Reuters)

This plane looks like it's bound for the moon as it shoots across the sky. Photographer Sebastien Lebrigand was impressed he could even see the lights on the jet's wings in this stunning silhouette. (Photo by Sebastien Lebrigand/Solent News)

Tim Laman is a field biologist and wildlife photojournalist. His pioneering research in the rain forest canopy in Borneo led to a PhD from Harvard and his first National Geographic article in 1997. Since then, he has pursued his passion for exploring wild places and documenting little-known and endangered wildlife by becoming a regular contributor to National Geographic. He has eighteen articles to his credit to date, all of which have had a conservation message. Some have focused on endangered species such as Orangutans or Hornbills, while others, such as a series of articles on Conservation International’s Biodiversity Hotspots, have highlighted regions under intense pressure.

Emperor penguins gathered together to keep their chicks warm in these pictures. Marine scientist Frederique Oliver snapped the protective parents in Antarctica as they huddled against the huge winds.The adorable birds have to battle temperatures on -20 degrees Celsius as well as winds of up to 40 knots on the ice. (Photo by Frederique Oliver/Caters News)

Children play on an abandoned car near a protest, which is against the dissolution of Yemen's parliament and the Shi'ite Muslim Houthi militia's tightening grip on power, in the southwestern city of Taiz, February 13, 2015. (Photo by Mohamed al-Sayaghi/Reuters)