A wolf skin is on display for sale next to a painting of Russian communist revolutionary Vladimir Ilyich Ulyanov, also known as Lenin, at Izmailovo flea market in Moscow on December 3, 2017. (Photo by Mladen Antonov/AFP Photo)

A four-week old southern three-banded armadillo (Tolypeutes matacus) is rolled up into a ball next to its mother in the tropical house of Budapest Zoo in Budapest, Hungary on May 3, 2019. The South American insect-eating mammal and its close relative, the Brasilian three-banded armadillo (Tolypeutes tricinctus) are the only two species of armadillos capable of rolling into a complete ball to defend themselves when feeling threatened. (Photo by Attila Kovács/EPA/EFE)

A fan of K-pop idol boy band BTS poses for photographs with cut-out of BTS at a pop-up store selling BTS goods in Seoul, South Korea, December 24, 2019. (Photo by Kim Hong-Ji/Reuters)

Models showcase Valentine's Day underwear celebrating the results of a recent survey revealing that men find the lingerie, boxer shorts and vests, the biggest turn on ahead of February 14 Valentine celebrations, at Waterloo on February 2, 2006 in London, England. (Photo by Gareth Cattermole/Getty Images)

The International Garden Photographer of the Year has announced the winner of their Black & White Photo Project 2019. Here: Blue Tit, Criccieth, Wales. (Photo by Alan Price/The International Garden Photographer of the Year)

Londoners sleep on the platform and on the train tracks at Aldwych Underground station,London, during heavy all night Nazi bombing raids, October 8, 1940. (Photo by AP Photo)

Tank crew standing in front of M-4 tank, Ft. Knox, Kentucky, June, 1942. (Alfred Palmer/OWI/LOC)

An aircraft passes the rising sun during take off at the international airport in Frankfurt, Germany, Monday, September 2, 2019. (Photo by Michael Probst/AP Photo)