A German Shepard bares its teeth during Schutzhund attack dog training at Witmer-Tyson Imports February 14, 2002 in Newark, CA. (Photo by Justin Sullivan/Getty Images)

Models of Cold War-era Allied (L) and Soviet Bloc weaponry face one another at the new Bundeswehr Military History Museum (Militaerhistorisches Museum der Bundeswehr, or MHM) on October 11, 2011 in Dresden, Germany. The museum, redesigned by star architect Daniel Libeskind, traces Germany military history from 1300 to the present, including during the Nazi period and the Cold War, and also examines the influence of the military on popular culture. (Photo by Sean Gallup/Getty Images)

Jeremy Scott backstage at the Jeremy Scott fall 2012 fashion show during Mercedes-Benz Fashion Week at Milk Studios on February 15, 2012 in New York City. (Photo by Craig Barritt/Getty Images)

A bride from the Santa Marta slum takes a break after getting her makeup done before a group wedding in Rio de Janeiro December 17, 2014. A total of 16 couples took part in a mass wedding ceremony organized by the Police Peacekeeping Unit (UPP) as part of activities geared towards social enhancement of the slums. (Photo by Pilar Olivares/Reuters)

Newborn orangutan Rieke is presented during a press conference at Berlin Zoo, in Berlin, Germany, February 6, 2015. The baby was born on January 12, 2015 weighing 2,290 grams and is bottle-fed by keepers. (Photo by Ralf Hirschberger/EPA)

These stunning coloured images show detailed x-ray images of everything from skulls to light bulbs. Artist Paula Fontaine, from Westminster Massachusetts, created the images using a process called digital map painting. To create the images the x-ray emission source – the head of the machine on an arm which focuses the beam – is placed over the object. Paula then retreats behind a shielded screen before activating the x-ray exposure. Here: Brain storm, conceptual composite X-ray. (Photo by Paula Fontaine/Barcroft Media)

A white Bengal tiger cub born in captivity is seen during a press presentation at Huachipa's private zoo in Lima, Peru, March 16, 2016. (Photo by Mariana Bazo/Reuters)

Tribesmen loyal to the Houthi movement perform the Baraa dance during a gathering to show support to the movement in Sanaa, Yemen, May 19, 2016. Bara or Baraa dance is one of the several traditional outdoor dances performed by men in the country of Yemen. Bara dance literally means a dagger dance, where each dancer holds a dagger. The style of the Bara dance differs from tribe to tribe. It is performed on special occasions. (Photo by Khaled Abdullah/Reuters)