A common gallinule runs across the water to escape a nearby alligator at Green Cay Nature Center in Boynton Beach, Florida on September 4, 2025. Unlike most waterbirds, gallinules have long toes that allow them to walk on floating vegetation. The species is known for its loud, cackling calls that often echo through wetlands. (Photo by Ronen Tivony/NurPhoto/Rex Features/Shutterstock)

This spiky tenrec was spotted in Madagascar’s Mantadia National Park in the last decade of September 2025. Mostly nocturnal and rarely seen, it puffs out its spines when threatened. Spiky tenrecs are excellent swimmers — unlike most spiny mammals, some species of tenrec can forage in streams and rivers, using their spines for protection while hunting aquatic insects and small prey. (Photo by Dale Morris/Solent News & Photo Agency)

Participants compete to do nothing during the Space-out competition at World Expo 2025 on September 27, 2025 in Osaka, Japan. For 90 minutes, participants sat in silence, trying to remain in a dazed state without distraction. The winner was determined not by activity but by calmness maintaining the most stable heart rate amid the lively crowds of the Osaka Expo site. (Photo by Tomohiro Ohsumi/Getty Images)

A Tibetan pilgrim prostrates herself at the Jokhang Temple in central Lhasa, Tibet Autonomous Region, China early November 20, 2015. Every day thousands of Tibetans visit and pray at Jokhang Temple, considered one of the most sacred places of worship. (Photo by Damir Sagolj/Reuters)

An operator adjusts a film projector during a wedding party in Bogor, Indonesia, February 18, 2017. Indonesian entrepreneur Kamaluddin loves the gritty look of old 35-millimeter film so much that he spends most of his nights screening vintage movies at weddings and parties around Jakarta, the capital. (Photo by Reuters/Beawiharta)

Members of Tom Maior Special Group samba school perform during the carnival parade at the Anhembi Sambadrome in Sao Paulo, Brazil, 22 Febr​uary 2020. Carnival is the biggest and most popular celebration in Brazil. (Photo by Sebastiao Moreira/EPA/EFE)

Lake Baikal is the world's oldest lake, at 25 million years (possibly older), and deepest, averaging 744.4 metres (2,442 ft).

Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the world, containing roughly 20% of the world's unfrozen surface fresh water.