United States Marine Corps Staff Sgt. Jason Itro yells at recruit Nancy Carbins January 15, 2003 after she grabbed another recruit in the pool in an attempt to stay afloat during swim training at the Combat Pool on Parris Island, SC. Under the watchful eyes of swim instructors, recruits are required to swim in full gear and learn limited strokes and breathing to stay afloat. Carbins broke a major rule by grabbing another recruit and submerging them both. (Photo by Stephen Morton/Getty Images)

“Amphilophus citrinellus is a large cichlid fish endemic to the San Juan River and adjacent watersheds in Costa Rica and Nicaragua. In the aquarium trade A. citrinellus is often sold under the trade name of Midas cichlid. A. citrinellus are omnivorous and their diet consists of plant material, molluscs and smaller fish”. – Wikipedia

Photo: Two Midas Cichlid (lat: amphilophus citrinellus) fish are seen in an aquarium at Hellabrunn zoo on December 23, 2009 in Munich, Germany. (Photo by Alexandra Beier/Getty Images)

Stunning silhouettes under European cities reveal the size and splendor of the continent’s urban foundations. Photographer and content-manager Anna Arinova, 28, from Moscow, captured the awe-inspiring labyrinths in Russia and Germany. Here: Regenwurmlager, Poland. The Regenwurmlager is an extensive underground fortification area constructed by Germany in 1920s-1940s, now in western Poland, near the city of Międzyrzecz. (Photo by Anna Arinova/Caters News)

The carcass of a fattened pig, winner of the “holy pig” contest, is attached to a metal frame during a sacrificial ceremony in Sanxia district, in New Taipei City, Taiwan February 1, 2017. The winner of Taiwan's “holy pig” ceremony on Thursday defended the lunar new year tradition against critics who argue the fattened animals are raised under cruel conditions. (Photo by Tyrone Siu/Reuters)

Participants in the Grelka Fest at the Sheregesh resort in Tashtagolsky District of Kemerovo Oblast, Russia on April 22, 2017. Russian girls marked the end of the ski season with a record-breaking bikini ski festival at Siberia’s top winter resort, Sheregesh. Some 1,498 skiers and snowboarders undressed to impress in the annual event as they took to the pistes under blues skies and sunshine in a bracing temperature of just 5°C. (Photo by Grelka Fest/The Siberian Times)

A hyena eyes a herd of zebra at Lake Nakuru National Park, Kenya, August 19, 2015. The Park is home to some of the world's most majestic wildlife including lions, rhinos, zebras and flamingos. The scenery is stunning, from forests of acacia trees to animals congregating at the shores to drink. UNESCO says that with rapid population growth nearby, the area is under "considerable threat from surrounding pressures," particularly deforestation, a contributing factor in floods. (Photo by Joe Penney/Reuters)

Members of the association historical recreation Frente del Nalon participate in the recreation of the battle: “The Siege of Oviedo” that took place during the Spanish Civil War, in Grullos, near Oviedo, in northern Spain, September 3, 2016. The Siege of Oviedo lasted from July 19 until October 16, 1936. The town garrison, under the command of Colonel Antonio Aranda Mata, declared for the uprising and held out until relieved by a Nationalist force. (Photo by Eloy Alonso/Reuters)

“These incredible shots show the stunning formations of an iceberg beneath the surface of the ocean. Taken in Tasiilaq, Greenland, by Franco Banfi, the underwater photography captures the beauty of these ice mountains beneath the ocean’s surface. In some of the photos, divers are swimming around an iceberg under the frozen water, while other images show some of the weird and wonderful creatures you can encounter in that part of the ocean”. (Photo by Franco Banfi/Caters News Agency)