World's Greatest Swimming Pools: Four Seasons, Serengeti Pool, Tanzania. A show of elephants, buffalo and baboons awaits thanks to an active watering hole below the free-form infinity pool at this plush hideaway inside Serengeti National Park. Bonus: Because of infrared technology at the hole, guests can be notified on their bedroom TV when animals are approaching. When you've got word of wildlife on the horizon, catch them from your private terrace – or head back to the pool. (From $1,650). (Photo by Four Seasons)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

Two women look at a mobile phone as they stand on Tiananmen Square during a sand storm in heavily polluted weather in Beijing on February 28, 2013. Beijing residents were urged to stay indoors as pollution levels soared before a sandstorm brought further misery to China's capital. (Photo by Ed Jones/AFP Photo)

Maudy – Kalulushi, Zambia. Maudy was born in a hut in a small village close to Kalulushi, in Zambia. She grew up playing in the street with the other children in the village, who all attend the same school, where students ages 3 to 10 years old are in the same class. The village has no shops, restaurants or hotels, and just a few children are lucky enough to have toys. Maudy and her friends found a box full of sunglasses on the street, which quickly became their favorite toys. “Toy Stories” project. (Photo and caption by Gabriele Galimberti)

Artist C. K. Wilde creates intricate collage compositions using pieces of paper currency from all over the world. His collages have referenced subjects ranging from space exploration, to mythology, religion, slavery, ecology, the history of warfare, the history of money, and art history. Photo: “Great Crash”. (Photo by C. K. Wilde)

The Bahamas, the Commonwealth nation of hundreds of islands roughly the size of Connecticut and with population of just a bit over Anaheim, is known for its crystal waters and pristine beaches. This is possibly one of the world’s most beautiful havens of nature, yet people are coming here to see pigs. It is unclear when the pigs first appeared on Exuma Island or where they come from. There’s talk about a daring escape from a shipwreck, or sailors releasing the swine on purpose. In all probability, there were no pigs on this tropical paradise before European settlers came, so their mere presence is the work of human. The intriguing feat of nature, however, is that this population of pigs developed a fine aptitude for swimming. Here: “So you're on a boat in Bahamas and then this pig swims by begging for food”. (Photo and caption by Lisa Larsen/Public Domain)

Close Encounter of the Insect Kind: “Check out the awesome face on this praying mantis. I can't get over the mouth, it's like something from a science fiction movie. Of all photographic styles macro is definitely my favorite. I am constantly amazed, in every photo that I take, by the intricate level of detail that exists on even the smallest of creatures. It's a stark reminder that a very complex and infinitely beautiful world exists just beyond our human-sized level of perception. Photo taken in Donnybrook, Queensland, Australia” – Andrew Young. (Photo by Andrew Young/National Geographic Photo Contest via The Atlantic)