Smithsonian National Zoo biologist Leigh Pitsko releases a male lion cub for its swim test in the zoo habitat moat, in Washington May 6, 2014. Four, unnamed ten-week old lion cubs were tested today for their ability to swim and remove themselves from their zoo habitat moat. (Photo by Gary Cameron/Reuters)

Four hundred buyers from around the world join 260 diamond manufacturing and trading firms on International Diamond Week as some 1,500 people are expected to trade more than billion of polished diamonds this week in Ramat Gan, Israel on February 16, 2016. The Israel Diamond Exchange is considered the most secure in the world, covering an area of 100,000 square meters with 3,500 bourse members. (Photo by Nir Alon via ZUMA Wire)

Actor Hugh Laurie arrives at the premiere of Universal Pictures and Illumination Entertainment's 'HOP' at CityWalk on March 27, 2011 in Universal City, California.

This week's full Moon as photographed from on board the International Space Station by NASA astronaut Jeff Williams on August 19, 2016. Jeff is currently Commander of the Space Station for the Expedition 48 crew. (Photo by Jeff Williams/NASA)

Some Iraqi candidates for Miss Iraq beauty contest pose in front of the Ishtar Gate at the ancient archaeological site of Babylon, outside the modern city of Hilla, south of the capital Baghdad on December 17, 2015. The beauty contest, which is the first one in more than 40 years, aims to boost tourism in the city and will take place on December 19, 2015. (Photo by Ahmad Al-Rubaye/AFP Photo)

Elena Ivanov, visiting from San Jose, Calif., walks across the field covered poppies in full bloom near the Antelope Valley California Poppy Reserve in Lancaster, Calif., Wednesday, March 30, 2022. (Photo by Jae C. Hong/AP Photo)

Creative imagery bronze winner. Make-up by Chengbo Sun, China. (Photo by BPOTY/Cover Images)

“They're some of the most intriguing and complex creatures on the planet but they really do have nothing to hide – because theyre totally see-through. Transparent animals – creatures with clear glass-like skin – can be found all over the world but their very existence is still shrouded in mystery. The fascinating organisms verge on the invisible and their translucent skin often helps them elude predators”. – Caters News. Photo: Thornback Skate. (Photo by Ken Lucas/Caters News)