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)

An employee looks at the artwork “4-Chlorephenol, 2008”, part of the artist Damien Hirst's exhibition “The Complete Spot Paintings” at the Gagosian Gallery on January 12, 2012 in London, England. (Photo by Matthew Lloyd/Getty Images)

South Korean workers are seen from a crane as they work on the 123rd floor during the framing completion ceremony of the 'Lotte World Tower' in Seoul, South Kora, 22 December 2015. The building's exterior was completed in a final height of 550 meters, and 123 floors. The ceremony came five years and two months after the construction of the building began and its opening will likely take place at the end of next year when the interior work is set to be completed, the South Korean Yonhap news agency reported. The building is the highest in South Korea and the fifth highest in the world, according to Yonhap. (Photo by Jeon Heon-Kyun/EPA)

A man takes photo of his colleague with a mobile phone on the burning oil tanker at the ship-breaking yard in Gaddani, Pakistan, November 2, 2016. Reports state that at least eighteen workers were killed and more than 100 were wounded in a blast at Gaddani ship breaking yard near Karachi on 01 November. Initial reports suggest the blast occurred when a gas cylinder exploded inside an oil tanker being broken up for scrap. (Photo by Akhtar Soomro/Reuters)

Models kiss the back of another model, with a message on her back, during the grand finale of Lotus Make-up India Fashion Week based on “Rainbow” theme, an emblem for the LGBTQ community, in New Delhi, India, Sunday, October 14, 2018. According to Fashion Design Council of India, the “Rainbow” show, wherein 40 designers showcased their creations, was a tribute to mark the historic judgement by the Supreme Court of India which struck down a colonial-era law that made homosexual acts punishable by up to 10 years in prison. (Photo by Altaf Qadri/AP Photo)

A suspected Vietcong is kicked by a Vietnamese soldier holding a rifle as another soldier attempts to tie his hands on October 22, 1965. The prisoner was one of 15 captured October 21 near Xom Chua when government troops raided in the plain of reeds area. Troops killed 43 suspected Vietcong and seized some arms. (Photo by Richard Merron/AP Photo)

Solana Plains (R) escorts a distraught Elijah West, cousin of Troy Davis, out of the Towaliga County Line Baptist Church that is across from the Jackson State Prison for the planned execution of inmate Troy Davis on September 21, 2011 in Jackson, Georgia. (Photo by Jessica McGowan/Getty Images)

Revellers take part in the annual “Naval Battle” of Vallecas in Madrid, Spain July 19, 2015. The slogan for this year's water battle is “Get wet for Alfon, freedom for Alfon”, referring to Alfonso Fernandez Ortega, a Vallecas resident who was sentenced to four years in prison in June. The festival was started spontaneously in 1981 when some neighbours started to throw water at one another due to high temperatures during the Virgen del Carmen Festival. (Photo by Juan Medina/Reuters)