In this January 27, 2015 photo, penguins walk on the shore of Bahia Almirantazgo in Antarctica. Antarctica “is big and it's changing and it affects the rest of the planet and we can't afford to ignore what's going on down there”, said David Vaughan, science director of the British Antarctic Survey. (Photo by Natacha Pisarenko/AP Photo)

A man dressed as a devil performs during a Krampus show, the traditional parade where people in costumes and masks perform an old ritual to disperse the ghosts of winter, in the southern Bohemian town of Kaplice, December 10, 2016. (Photo by David W. Cerny/Reuters)

Zurab Gurielidze, a director of the Tbilisi Zoo, speaks to the media while standing next to a hippopotamus named Begi at the zoo in Tbilisi, Georgia, September 13, 2015. Tbilisi zoo, which was partly destroyed and some 300 animals escaped or died in the floods that also killed at least 19 people in June, was reopened on Sunday. (Photo by David Mdzinarishvili/Reuters)

A man watches the approaching flames as the Springs fire continues to grow near Camarillo, California, on May 3, 2013. The wildfire has spread to more than 18,000 acres on day two and is 20 percent contained. (Photo by David McNew)

Handout grab taken from YouTube of Commander Chris Hadfield who has said goodbye to life on the International Space Station by making a cover version of David Bowie's Space Oddity. Issue date: Monday May 13, 2013. (Photo by Commander Chris Hadfield/YouTube/PA Wire)

“Thunderstruck”. Summer stom. A super cell formed off the coast of New Zealand, intensified and swept across Christchurch and North Canterbury, February 23, 2014. Photo location: Christchurch, New Zealand. (Photo and caption by David Hardy/National Geographic Photo Contest)

Tiffany Porter of Britain falls after competing in the women's 100 metres hurdles final during the 15th IAAF World Championships at the National Stadium in Beijing, China August 28, 2015. (Photo by David Gray/Reuters)

They say a picture is worth a thousand words, and these striking images of 2017 are no exception. The photo highlights include incredible snapshots of the natural world as well as some awesome animal and human encounters. The vibrant gallery also shows thrill-seekers pushing themselves to the limit with breathtaking stunts captured in perfect clarity. The pictures have been taken by a host of photographers from around the world. Here: The two lion cubs singing their hearts out at Antelope park in Zimbabwe. (Photo by David Jenkins/Caters News Agency)