Meerkats are weighed and measured during the ZSL London Zoo 's annual weigh-in on August 22, 2012 in London, England. The height and mass of every animal in the zoo, of which there are over 16,000, needs to be recorded. The measurements are collated in the Zoological Information Management System, from which zoologists can use the data to compare information on thousands of endangered species. (Photo by Oli Scarff)

A flock of Adjutants storks sit on a garbage dump at Borgaon in Guwahati, Assam, India, 17 October 2019. Wildlife activists and environmentalists have protested in the past for shifting the garbage dump to another site since it is situated near the Deepor Beel Bird Sanctuary. (Photo by EPA/EFE/Stringer)

People take a selfie at the abandoned former Soviet R12 nuclear missile launch site in Zeltini, Latvia, July 22, 2016. Hidden in the forests of Aluksne, near Latvia's north-eastern border with Russia, the remains of a former Soviet nuclear missile base are a magnet for tourists now rather than a top-secret site manned by soldiers. (Photo by Ints Kalnins/Reuters)

Reuters South Africa-based photographer Juda Ngwenya who documented Nelson Mandela's historic rise to power died on Wednesday. Here: Prostitutes wait at a bar in a plush northern suburb of Johannesburg August 22, 2002. (Photo by Juda Ngwenya/Reuters)

Beach Policeman, Potomac River, 1922. (Photo by National Photo Company/Colorized by Patty Allison)

Li Tingting, second from right, laughs as she is lifted off the ground by her wife Teresa Xu, right, outside of a beauty salon where the two were preparing for their wedding as clerks from an adjacent shop look on in Beijing, Thursday, July 2, 2015. Li, a 25-year-old prominent women's rights activist who was released from detention in April, held the wedding ceremony with her partner Teresa on Thursday and announced their marriage in an effort to push for LGBT (lesbian, gay, bisexual, and transgender) rights in China. (Photo by Mark Schiefelbein/AP Photo)