People follow king penguins exploring their outdoor pen, during a so-called “penguin parade”, when the animals walk outside their enclosure and the visitors can walk behind them, at Zurich's Zoo in Zurich, Switzerland January 28, 2017. (Photo by Arnd Wiegmann/Reuters)

A busy rush hour sees thousands of commuters climbing on board a train – as well as holding onto its sides and sitting on the roof before it speeds off. Men, women and children climb and are pulled up onto the roof of the train, which is around 12ft (3.6m) high, as they try to find themselves a space. With no seats available inside, many commuters decide to take the risk and choose a rooftop view for their journey out of Dhaka city, in Bangladesh. (Photo by Yousuf Tushar/Solent News & Photo Agency)

In this photo taken on Saturday, April 22, 2017, a drawing “King for a day” is made on the back of a muddy truck by artist Nikita Golubev in Moscow, Russia. The grimy trucks traversing the polluted and dusty streets of Moscow have inspired Golubev to use white vans and trucks as his canvas to create this ephemeral street art and signs his drawings Pro Boy Nick. (Photo by Pavel Golovkin/AP Photo)

Women demonstrate on International Women's Day as they strike to demand the end to domestic violence and the country's prevailing “macho” culture, in Milan, Italy on March 8, 2023. (Photo by Claudia Greco/Reuters)

Naked Sushi event where people eat sushi from the bodies of nearly naked models at Buddha Bar, Knightsbridge in London, United Kingdom. (Photo by Alamy Stock Photo)

The Malabar Giant squirrel – double the size of their grey relatives and measuring up to 36 inches (91.5 cm) from head to tail – lives deep in the forests of India. The athletic animals can leap an incredible 20 feet (6 m) between trees. Photographer Kaushik Vijayan, 39, snapped the animals in their native habit to produce these stunning images. Kaushik, from Kerala State, India, said: “Up until that point I had never heard about a squirrel like that or seen one. The sight was an absolute feast for my eyes. The squirrels fascinated me and I got excited to capture this beauty on my camera”. (Photo by Kaushik Vijayan/South West News Service)

“Tea Hills”. Early-morning mist over the tea hills of Phu Tho province in Vietnam. (Photo by Vu Trung Huan/Royal Meteorological Society’s Weather Photographer of the Year Awards)

“Aurora Hunters”. Photographers taking part in a photography tour on the Lofoten Islands in Norway, pull over on the side of the road to take a photo of their first ever Aurora Borealis after spotting it from their tour bus. Photo location: Rystad, Lofoten Islands, Norway. (Photo and caption by Mark Gee/National Geographic Photo Contest)