Shooting star by Tony Wu, US/Japan. Winner, underwater. The electrifying reproductive dance of a giant sea star. As the surrounding water filled with sperm and eggs from spawning sea stars, Wu faced several challenges. Stuck in a small, enclosed bay with only a macro lens for photographing small subjects, he backed up to squeeze the undulating sea star into his field of view. The dancing posture of spawning sea stars rising and swaying may help release eggs and sperm, or may help sweep the eggs and sperm into the currents where they fertilise together in the water. Kinko Bay, Japan. (Photo by Tony Wu/Wildlife Photographer of the Year)

A devotee of the Hare Krishna faith poses for a photograph during the festival of Rathayatra on June 12, 2011 in London, England. Rathayatra, or Chariot festival, features three huge, wooden chariots pulled by hand across Central London accompanied by constant singing, chanting, drums, cymbals and dancing. (Photo by Matthew Lloyd/Getty Images)

Santa Students practice dancing during the Charles W. Howard Santa Claus School workshop on October 16, 2008 in Midland, Michigan. (Photo by Al Bello/Getty Images)

Francisco Solano poses for a photo in his bird-feather suit after attending a Mass commemorating the feast day of St. Francis Solano, in Emboscada, Paraguay, Friday, July 24, 2015. Some 500 people attended the festivity – a mix of indigenous and Guarani Indian beliefs. The festival begins with a Mass, continues with a procession of the diminutive wooden statue of St. Francis, and ends with people dancing in suits made with black, white, brown and grey feathers. (Photo by Jorge Saenz/AP Photo)

In this November 11, 2017 photo, children dressed in traditional outfits play during the Azorean Culture Festival which celebrates the culture of the Azores, the Portuguese island chain in the mid-Atlantic, in Enseada de Brito, in Brazil's Santa Catarina southern state. “We have to make sure that our culture always stays alive, not let it die”, said Andre Cordeiro, who leads one of the singing and dancing groups that performed this year. “We are able to pass it on from generation to generation”. (Photo by Eraldo Peres/AP Photo)

A picture made available on 13 May 2016 shows A Tiwa girl performing her traditional dance as they celebrated the Wanchuwa festival in Karbi Anglong District of Assam state, India, 11 May 2016. Wanchuwa is one of the most important festivals of the Tiwa tribal community living in the hills as it is related with agriculture which is the mainstay of their economy. Tiwas pray for a bountiful harvest during this festival and to protect their crops from pest and other natural calamities. Tiwa is a major tribe of Assam state who practice Jhum or shifting cultivation for their living in the hills. (Photo by EPA/Stringer)

Florin Bors, aged 8 from Bacau, northern Romania, wearing a bear fur takes a break from performing a holiday season ritual in Bucharest, Romania, Tuesday, December 16, 2014. In pre-Christian rural traditions, dancers wearing colored costumes or animal furs, touring house to house in villages singing and dancing to ward off evil. In recent years following the economic downturn in Romania, a European Union member since 2007, the tradition has moved to Romania's cities where dancers travel to perform the ritual for money. (Photo by Octav Ganea/AP Photo/Mediafax)

Pakistani Waseem Akram, 27, dances during a private party in Rawalpindi, Pakistan. By day, Akram sells mobile phone accessories from an alleyway shop in an old neighborhood of this Pakistani city, Thursday, January 15, 2015. Across conservative Pakistan, where Islamic extremists launch near-daily attacks and many follow a strict interpretation of their Muslim faith, male cross-dressers and the transgendered face a challenge of balancing two identities. Some left their villages for the anonymity of a big city, fearing the reactions of their families while still concealing their identity from neighbors and co-workers. (Photo by Muhammed Muheisen/AP Photo)