March 11, 2008 Swiss car manufacturer Rinspeed made quite the splash at the Geneva Motor Show with its innovative sQuba, a fully functional submersible concept car that cost $1.5 million to build. (Photo by Rinspeed)

Ginger Stanley performs a grand jete during her solo underwater ballet at Silver Springs, Florida. (Photo by Bruce Mozert/Three Lions/Getty Images). Circa 1956

Seth Casteel is an award-winning photographer and the New York Times Best Selling Author of Underwater Dogs. His new book, Underwater Puppies, was published September 16, 2014. Photo: “Underwater Puppies”: Popcicle. (Photo by Seth Casteel)

Artist Jason deCaires Taylor’s Museo Atlantico, off Lanzarote, is peopled with concrete casts of refugees and people taking selfies. Drowned world: welcome to Europe’s first undersea sculpture museum. Here: The Raft of Lampedusa, Taylor’s modern-day concrete echo of Géricault’s The Raft of the Medusa. The work has particular significance given the huge movement of refugees across the sea to Europe – and the frequent fatalities that result. (Photo by Jason deCaires Taylor)

Claire Robertson from Scottish Ballet, poses dressed as the Good Snow Flake inside a life size snow globe on Buchanan Street during a promotion for Scottish Ballet’s festive production of The Nutcracker on November 20, 2012 in Glasgow, Scotland. The Nutcracker opens at the Theatre Royal on December the 8th, the production delves deep into the darker reaches of Hoffmann’s original tale in a fresh and vivid retelling of the famous Christmas story. (Photo by Jeff J. Mitchell)

A Hawaiian cleaner wrasse provides its cleaning services to a yellowfin goatfish in a reef community off the Big Island in Hawaii. Cleaner species help rid their hosts of ectoparasites, dead tissue, bacteria and fungi. Studies have shown cleaning to play a vital role in keeping many reef ecosystems healthy. (Photo by Marty Snyderman/Caters News Agency)

A woman dives and pretends to ride a bike in Underwater Park in Pula, Croatia, August 1, 2017. (Photo by Antonio Bronic/Reuters)