A fighting bull loses its balance during the third day of the San Fermin running-of-the-bulls on July 8, 2011 in Pamplona, Spain. Pamplona's famous Fiesta de San Fermin, which involves the running of the bulls through the historic heart of Pamplona for eight days starting July 7th, was made famous by the 1926 novel of U.S. writer Ernest Hemmingway called “The Sun Also Rises”. (Photo by Denis Doyle/Getty Images)

“Sperm whale opening it's huge mouth, Ogasawara Islands, Japan. Sperm whales are the biggest carnivorous animals on the planet. Each teeth in the mouth of adult specimen weights more than 1 kilogram. Interestingly enough that modern marine biologists believe that these teeth despite being fearsome play little role in capturing and eating giant squid – with their main function being mainly ritual aggression between males!”. (Photo by Alexander Safonov)

Labourers stack dried bricks inside a kiln, where they will be fired, at a brick factory on the outskirt of Sanaa, Yemen, June 1, 2016. Traditional mud brick tower houses have always been a source of pride to Yemenis, and over a year into a devastating civil war, they are also providing some much-needed jobs in the ancient capital Sanaa. (Photo by Mohamed al-Sayaghi/Reuters)

Paul, 9, dumps a bucket of water over his head at a fountain near government buildings during hot weather on July 1, 2015 in Berlin, Germany. Temperatures across northern Europe are rising and in Germany a high of 36 degrees is forecast for the weekend. (Photo by Sean Gallup/Getty Images)

Local residents crowd a swimming pool during a hot weather in Suining, Sichuan province, 27 July 2008. (Photo by Reuters/Stringer)

North Korean traffic police women chat next to a residential building while off duty Tuesday, October 18, 2016, in Pyongyang, North Korea. (Photo by Wong Maye-E/AP Photo)

Gymnast Valeria Kurochkina from Yekaterinburg performs during the Circus of Our Childhood festival at the Yekaterinburg Circus in Yekaterinburg, Russia on December 7, 2019. The festival marks the centenary of establishing state circuses in Russia. (Photo by Donat Sorokin/TASS)

People participate in the annual “No Pants Subway Ride” in New York City, U.S., January 12, 2020. (Photo by Brendan McDermid/Reuters)