World medieval jousting champion Rod Walker poses before next month’s St Ives Medieval Faire, the only solid wood lance joust tournament in the southern hemisphere in Sydney, Australia on August 26, 2016. (Photo by Dan Himbrechts/AAP)

A giant river otter, the world's largest otter species, looks out of its enclosure at the newly completed River Safari in Singapore, on March 25, 2013. (Photo by Wong Maye-E/Associated Press)

A child dressed as a clown takes part in the celebration of the Virgen de los Desamparados, or Our Lady of the Abandoned, at Diria town, Nicaragua May 14, 2016. (Photo by Oswaldo Rivas/Reuters)

Russian Foreign Ministry spokeswoman Maria Zakharova dances during the reception in honour of heads of the delegations at the Russia-ASEAN summit in Sochi, Russia, May 19, 2016. (Photo by Host photo agency via Reuters)

An undated handout picture released on January 10, 2017 by the Issekinicho publishing house shows an inter- species sexual behaviour between a male Japanese macaque and female sika deer, in Yakushima Scientists revealed on January 10, 2017 the “highly unusual” behaviour of a male monkey filmed trying to have sеx with female deer in Japan – a rare case of inter- species nookie. (Photo by Editions Issekinicho/AFP Photo)

An inmate (L) tends to a fellow prisoner while performing ear candling during an alternative therapy session as part of the ACUDA programme, at a complex of ten prisons in Porto Velho, Rondonia State, Brazil, August 27, 2015. Ear candling, which involves inserting a hollow cone-shaped device into the ear canal and lighting the exposed end, is believed by practitioners to draw out earwax. According to ACUDA the therapy is beneficial for the inmates' emotional health. (Photo by Nacho Doce/Reuters)

This picture taken on October 20, 2016 shows students practising wushu at the Tagou martial arts school in Dengfeng. China is investing hugely in football training and has vowed to have 50 million school- age players by 2020, as the ruling Communist party eyes “football superpower” status by 2050. (Photo by Nicolas Asfouri/AFP Photo)

This photo take on December 16, 2016 shows macaques monkeys playing on a motorbike in the grounds of a temple in Jaipur in the Indian state of Rajasthan. (Photo by Dominique Faget/AFP Photo)