A dead whale is seen on the shore of the Ipanema beach in Rio de Janeiro, Brazil November 15, 2017. A biologist, Rafael Carvalho, said on Wednesday the whale appeared to have been dead for a few days. Authorities were urging beachgoers who had flocked to Ipanema on a national holiday to stay away from the animal. However, many were spotted near the carcass with some people playing in the water nearby. The whale is approximately 39 feet (12 metres) long and weighs about 25 tonnes. (Photo by Pilar Olivares/Reuters)

A woman walks past posters bearing the letter “Z” in the colours of the ribbon of Saint George, which has become a symbol of support for Russian military action in Ukraine, and reading “We are proud of Russia! We are not ashamed!” at a bus stop on Nevsky Prospekt in central Saint Petersburg on March 15, 2022. (Photo by AFP Photo/Stringer)

Meet the star students of orangutan school – the unique rehab centre where orphaned apes are taught how to climb trees and survive in the wild without their mum and dad. (Photo by Caters News)

Relatives mourn over the shrouded body of Mohammad Abed, who is killed in an Israeli airstrike on a shelter in Gaza City, during his funeral in Gaza City, on April 19, 2025. (Photo by Majdi Fathi/NurPhoto/Rex Features/Shutterstock)

Honor guards are viewed during an official welcoming ceremony for Turkish President Recep Tayyip Erdogan by Albanian President Bajram Begaj, in Tirana, Albania on October 10, 2024. Turkish President Recep Tayyip Erdogan was welcomed by Albanian President Bajram Begaj with an official ceremony ahead of their meeting. (Photo by Mehmet Ali Ozcan/Anadolu via Getty Images)

A South Korea university student gets her head shaved during a protest against Japan's decision to release contaminated water from its crippled Fukushima nuclear plant into the sea, in front of the Japanese embassy, in Seoul, South Korea, April 20, 2021. (Photo by Kim Hong-ji/Reuters)

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.

A penguin (Manchots Royaux) walks on the basement area, early morning on December 25, 2022, at the Kerguelen Islands, also known as the Desolation Islands, are a group of islands in the sub-Antarctic. (Photo by Patrick Hertzog/AFP Photo)