Folk artist Han Xiaoming demonstrates painting with his tongue in Hangzhou, Zhejiang province December 4, 2014. Han dips his tongue in ink to paint on paper, and uses his fingers to fill in final adjustments. The artist also uses a paintbrush held with his mouth and utilizes fish and vegetables as paint tools, local media reported. (Photo by Aly Song/Reuters)

“Asaro from the Eastern Highlands”. The mudmen could not cover their faces with mud because the people of Papua New Guinea thought that the mud from the Asaro river was poisonous. So instead of covering their faces with this alleged poison, they made masks from pebbles that they heated and water from the waterfall, with unusual designs such as long or very short ears either going down to the chin or sticking up at the top, long joined eyebrows attached to the top of the ears, horns and sideways mouths. (Photo and caption by Jimmy Nelson)

This April 30, 2016 image made available by NOAA shows a deep sea anglerfish living between pillow basalt rock formations, during a deepwater exploration of the Marianas Trench Marine National Monument area in the Pacific Ocean near Guam and Saipan. The ambush predator waits for prey to be attracted by its lure, located between its eyes, and gulps it with its large mouth. (Photo by NOAA Office of Ocean Exploration and Research via AP Photo)

Turbines of the new Burbo Bank off shore wind farm lay in the wake of a maintenance boat in the mouth of the River Mersey on May 12, 2008 in Liverpool, England. (Photo by Christopher Furlong/Getty Images)

Jacob's Well is a perennial karstic spring in the Texas Hill Country flowing from the bed of Cypress Creek, located northwest of Wimberley, Texas. The twelve foot (four meter) diameter mouth of the spring serves as a popular swimming spot for the local land owners whose properties adjoin Cypress Creek. From the opening in the creek bed, Jacob's Well cave descends vertically for about thirty feet (ten meters), then continues downward at an angle through a series of silted chambers separated by narrow restrictions, finally reaching a depth of one hundred and twenty feet (forty meters). Until the modern era, the Trinity Aquifer-fed natural artesian spring gushed water from the mouth of the cave, with a measured flow in 1924 of one hundred and seventy gallons per second (six hundred and forty liters per second) discharging six feet (two meters) into the air. The spring is the greatest source of water recharging the Edwards Aquifer.

This diver almost got sucked into the mouth of a massive whale shark as it feeds on plankton. But far from staring into the jaws of death – the shark, which are the sea's largest fish, is actually vegetarian. The relieved diver escaped from the encounter unscathed and continued to enjoy the presence of the incredibly docile animals. The stunning photograph, by Mauricio Handler, was taken during a feeding session where more than 600 of the huge creatures gathered to feed on tuna spawn. (Photo by Mauricio Handler/Daily Mail/Solent)

Bronze whaler shark (Carcharhinus brachyurus), caught in traditional seine net and released by fisherman, Muizenberg beach, Cape Town, South Africa on October 11, 2016. Action shots have captured fishermen trying to free a potentially deadly Bronze Whaler shark who was caught in their nets. The incredible images show the eight-foot-long 500-pound predator lunging its mouth towards the fishermen who are desperately trying to pull it back into the safety of the sea by its tail. Eventually they succeeded. (Photo by Chris and Monique Fallows/NPL)

Photographer Lucy Ray says she has been scratched by the pooches who are diving underwater to try and catch a tennis ball. Their wide-eyed desperation has been captured by a specialist underwater photographer who admits she has been bitten and scratched by the pooches who only had eyes for the ball. Lucy Ray, 34, said: “A dog could have the cutest face on land but as soon as they get in the water they can be terrifying. Their eyes bulge and teeth shoot out of their mouth just like an alien as they try to catch the ball”. (Photo by Lucy Ray)