The fangtooth has the largest teeth relative to body size of any fish in the ocean. (Photo by Espen Rekdal/BBC Pictures' Digital Picture Service)





In this February 14, 2017 photo provided by the Center for Coastal Studies, a pair of right whales feed just below the surface of Cape Cod Bay off shore from Provincetown, Mass. Charles “Stormy” Mayo, director of right whale ecology at center in Provincetown, said ominous signs suggest the global population of 500 animals is slowly declining. (Photo by Center for Coastal Studies via AP Photo)





Anchovies eat plastic because it smells like their prey. (Photo by Proceedings of the Royal Society B​ journal​)





A whale shark swims past a reef near the island of Koh Phangan, Thailand. (Photo by Dan Charity/The Guardian)





Coral, urchin, and the Easter Island butterflyfish, or white-tip butterflyfish, a subtropical fish in the Chaetodontidae family. It is endemic to the seas around Easter Island, 2,200 miles off the coast of mainland Chile. (Photo by Pew Trust)





A Portuguese man o’ war. Record numbers of the potentially fatal creature have washed up on the Cornish coastline, causing lifeguards to close a beach and issue safety advice. (Photo by Cornwall Wildlife Trust/PA Wire)





Hawaiian green sea turtles cruising in the warm waters of the Pacific. (Photo by Shane Myers/Alamy Stock Photo)





An employee watches a sea turtle from inside a glass tunnel, during the annual stock taking, at the aquarium operated by Britain's Sea Life Centers in Munich, Germany January 10, 2017. (Photo by Michael Dalder/Reuters)





A scuba diver is surrounded by schools of Silversides in the Devil's Grotto area near George Town, Cayman Islands, August 7, 2017. Each year, for only a few weeks, these schools form massive pulsating clouds in the caves, tunnels and swim-throughs, according to researchers. (Photo by Reuters/Courtesy of Predrag Vuckovic)





A still image shows a curious great white shark moves a camera around the sea bed while it is captured in action by another, near the Kermadec Islands, New Zealand, in this July, 2017 video released by Massey University on October 27, 2017. (Photo by Reuters/Massey University)





This undated photo made available by Julius Nielsen on August 11, 2016 shows a Greenland shark in the icy waters of Disko Bay, western Greenland. In a report released Thursday, Aug. 11, 2016, scientists calculate this species of shark is Earth’s oldest living animal with a backbone. They estimate that one of those they examined was born roughly 400 years ago, about the time of the Pilgrims in the U.S., and kept on swimming until it died only a couple years ago. (Photo by Julius Nielsen via AP Photo)





A snap was taken of this basking shark off the coast of the Isle of Coll, Scotland. (Photo by Grant Henderson/Alamy Stock Photo)





Open jaws of a Great White Shark Carcharodon Carcharias, South Africa. (Photo by Stephen Frink Collection/Alamy Stock Photo)





Sand tiger shark, Carcharias taurus, captive. (Photo by Mark Conlin/Alamy Stock Photo)





Great White Shark (Carcharodon carcharias), Dyer Island, South Africa – Atlantic Ocean. (Photo by Jeff Rotman/Getty Images)





This snap happy divers career is going swimmingly – thanks to these hilarious underwater selfies with a variety of marine life. Despite being a recent craze, Gary Brennand, 48, has been taking the funny photos for more than a decade. Adventurous Gary, from Perth, Australia, has photographed himself with everything from turtles to whale sharks and even barracudas. The diving instructor revealed 10 years ago not many people owned underwater camera gear so other people couldnt take shots of him. So whenever a sea creature dropped by hed turn the camera and take a picture of himself. (Photo by Caters News)





Photographer Tanya Houppermans described one of the images she was able to capture as a one in a million shot. Photographed from beneath a sand tiger shark, the image shows the animal as it penetrates a bait ball of thousands of fish, the top half of its body emerging out of the grouping near South Carolina, US. In other images, Tanya, 44, was able to capture the sharks as the moved between what look like tunnels made within the bait balls. (Photo by Tanya Houppermans/Caters News Agency)





A performer practices her mermaid swim next to a shark in an aquarium after graduating from a mermaid workshop in Guangzhou, Guangdong Province, China December 16, 2016. (Photo by Tyrone Siu/Reuters)