An employee at Christie's auction house examines a complete sub-fossilised elephant bird egg on March 27, 2013 in London, England. The elephant bird egg is expected to fetch 30,000 GBP when it features in Christie's “Travel, Science and Natural History” sale, which is to be held on April 24, 2013 in London. (Photo by Oli Scarff)

“I have seen batches of banknotes worth more than $2.6 million, but beyond all doubt, gold bars look much more attractive!”. – Shamil Zhumatov. Photo: Cooling-down gold ingot. March 14, 2013; Tien Shan mountains, Kyrgyzstan. (Photo by Shamil Zhumatov/Reuters)

A 42-day-old white bengal tiger cub (bottom), the first of its kind born in Peru, sleeps between toys as he is presented at the Huachipa's zoo in Lima on August 6, 2013. (Photo by Ernesto Benavides/AFP Photo)

A colourful sky before sunrise on Whitley Bay beach on December 21, 2015, as December could be the mildest across a large part of England since records began more than 350 years ago, forecasters have said. (Photo by Owen Humphreys/PA Wire)

Martin Lacey Jr. with a lion during the premiere of the Circus Krone program “Circus der Preistraeger” at Circus Krone on February 2, 2016 in Munich, Germany. (Photo by Hannes Magerstaedt/Getty Images)

A boy tumbles as he plays soccer on the streets of the Khayelitsha township in Cape Town, December 3, 2009. (Photo by Kai Pfaffenbach/Reuters)

A grasshopper rests on a photographic camera during a meeting in the village of Alto Jamari called to face the threat of armed land grabbers invading the Uru-eu-wau-wau Indigenous Reservation near Campo Novo de Rondonia, Brazil on January 30, 2019. (Photo by Ueslei Marcelino/Reuters)

In this photo taken on Thursday, March 7, 2019, the sun rises over the star on the spire on top of a Stalin-era skyscraper, now the Radisson Royal Hotel on the banks of the Moskva River in Moscow, Russia. (Photo by Dmitry Serebryakov/AP Photo)