Karis, an eleven week old lion cub, plays in fallen leaves brushed up by keepers in her enclosure at Blair Drummond Safari Park, near Stirling, Scotland, on November 20, 2013. (Photo by Andrew Milligan/PA Wire)

Mikhail Kalashnikov, the father of the world's most popular assault rifle, is handed an AK-74 November 23, 2002 in Izhevsk,1000 East km. from Moscow. November 23 marked the 55th anniversary of the release of the first Kalashnikov gun. According to the Moscow-based Center for Analysis of Strategic and Technologies some 70 million to 100 million Kalashnikovs have been built worldwide since 1947, compared about 7 million to Kalashnikov's Western rival the M-16 assault rifles. (Photo by Oleg Nikishin/Getty Images)

Gorillas at Royal Burgers’ Zoo, Arnhem, Netherlands, on November 28, 2013. (Photo by Vidi Photo/Startraks Photo New York)

Dilwyn Green, from North Wales, holds his 7 month old Gold Silkie Bantam which won a 1st prize in its breed at the Poultry Club's 2011 National Show on November 19, 2011 in Stoneleigh, England. (Photo by Oli Scarff/Getty Images)

LCR Honda IDEMITSU's Japanese rider Takaaki Nakagami crashes in the second MotoGP free practice session of the Portuguese Grand Prix at the Algarve International Circuit in Portimao, on April 16, 2021. (Photo by Patricia de Melo Moreira/AFP Photo)

Spot, a robot with dog-like movements, walks past a dog in Cathedral Square in Erfurt, Germany on April 20, 2021. Security service provider Ciborius, a provider of robotic security solutions with artificial intelligence, presented its artificial employee with high-resolution 360-degree all-round camera, ultra-bright LED light and a light detection system on Domplatz. (Photo by Michael Reichel/dpa)

A girl practices martial arts during a training at a school in Syrian opposition-held village of al-Jeineh, Syria on April 11, 2021. (Photo by Khalil Ashawi/Reuters)

Two displaced Tigrayan girls giggle next to their mother, left, as their photograph is taken outside the Hadnet General Secondary School which has become a makeshift home to thousands displaced by the conflict, in Mekele, in the Tigray region of northern Ethiopia Wednesday, May 5, 2021. The Tigray conflict has displaced more than 1 million people, the International Organization for Migration reported in April, and the numbers continue to rise. (Photo by Ben Curtis/AP Photo)