Hooded demonstrators vandalise a shop window in Mexico City, during the commemoration of the 50th anniversary of the 1968 Tlatelolco student massacre, on October 2, 2018. Fifty years ago, Mexican troops opened fire on student demonstrators, killing hundreds just days before Mexico City hosted the 1968 Olympics – one of the darkest episodes in a year of global turbulence. (Photo by Ronaldo Schemidt/AFP Photo)

Tech. Sgt. Milo Hinson, 3rd Combat Camera Squadron, uses a flashlight while shooting a Berretta 9mm during the night-fire portion of Advance Weapons, Tactics and Techniques training in San Antonio. During night-fire training, airmen learn how to tactically illuminate targets with flashlights and practice using night vision goggles. (Photo by Staff Sgt. Jonathan Snyder/U.S. Air Force). 2011

More than 700 underwater images were submitted for the 2012 Annual Underwater Photography Contest, hosted by the University of Miami's Rosenstiel School of Marine & Atmospheric Science. This year, for the first time, the University of Miami set up a “Fan Favorite” category for its underwater photo competition. Internet users could vote for their favorite among five pictures. Todd Aki's photo of a jellyfish took the prize, snaring 599 of the 1,221 votes cast. (Photo by Todd Aki)

No. 10: Sphynx. A suede-like coat is the sphynx's most unmistakable feature, but he's also curious, smart and a clown who craves applause for his antics. In fact, he loves attention so much that you may want to consider getting him a fellow sphynx playmate. (Photo by Quentin Descotte)

In this March 3, 2015 photo, a group of California sea lions rest on a large bouy in the San Ignacio lagoon, in the Pacific Ocean, near Guerrero Negro, in Mexico's Baja California peninsula. (Photo by Dario Lopez-Mills/AP Photo)

Tattoo artists and body art fans from across the globe have descended on London for one of the biggest and most prestigious tattoo conventions. “This is like the Premier League of tattoo artists from all over the world who come here to show their work”, organiser Marcus Beriman said. Photo: Bugz Bonniie displays some of her tattoos. (Photo by Oli Scarff)

Australian model Kate Fischer (Tziporah Malkah) poses with a Cointreau Ball to celebrate France’s founding anniversary in Sydney, Australia on July 14, 1996. (Photo by Getty Images)

(L-R) Canadian actor Patrick J. Adams as Michael Ross and American member of the British royal family and a former actress Meghan Markle as Rachel Zane at “Breakfast, Lunch and Dinner”, Episode 402 in April 2014. (Photo by Ian Watson/USA Network/NBCU Photo Bank/NBCUniversal via Getty Images)