A tribal fighter loyal to Yemen's government stands in Al Khurais village of Nihm district east of the capital Sanaa January 11, 2016. (Photo by Ali Owidha/Reuters)

UFC women's bantamweight champion Holly Holm and Miesha Tate face off during the UFC 196 weigh ins at the MGM Grand Garden Arena in Las Vegas on Friday, March 4, 2016. (Photo by L.E. Baskow/Las Vegas Sun via AP Photo)

Marieke van der Meer from the Netherlands works on her sculpture “Flora” at the sand sculpture show in Binz on Ruegen island, Germany, 09 March 2016. With the motto “Fascination Nature”, 50 sand artists have created oversized sculptures. The sculptors use 16,000 tons of special sand that is pressed into big blocks first and then formed. The 7th sand sculpture show on 5,600 square meters of exhibition ground opens on 12 March 2016. (Photo by Ens Buettner/EPA)

A worker loads palm fruit at a palm oil plantation in North Mamuju regency, West Sulawesi province, Indonesia March 10, 2016 in this photo taken by Antara Foto. (Photo by Sahrul Manda Tikupadang/Reuters/Antara Foto)

A competitor walks on tightrope during a performance in Taizhou, Zhejiang Province, China, May 7, 2016. (Photo by Reuters/China Daily)

Russian policewomen dressed in Soviet Army styled uniforms take part in the Victory Day parade in Volgograd on May 9, 2018. Russia marks the 73 rd anniversary of the Soviet Union' s victory over Nazi Germany in World War Two. (Photo by Mladen Antonov/AFP Photo)

Festival goers attend day one of the Parklife Festival at Heaton Park on June 9, 2018 in Manchester, England. (Photo by Mercury Press)

A boy sits on the back of a crocodile on May 19, 2018 at a pond in Bazoule in Burkina Faso, a village which happily shares its local pond with “sacred” crocodiles. Crocodiles may be one of the deadliest hunters in the animal kingdom, but in a small village in Burkina Faso it is not unusual to see someone sitting atop one of the fearsome reptiles. According to local legend, the startling relationship with the predators dates back to at least the 15 th century. The village was in the grip of an agonising drought until the crocodiles led women to a hidden pond where the population could slake their thirst. (Photo by Olympia de Maismont/AFP Photo)