Todd Bretl specializes in underwater photography, and is able to capture striking photos of aquatic life big and small. His photos of sharks are particularly striking; though he rarely faces hostility from the animals, he tries not to spend too much time looking through his viewfinder and many shots are framed by educated guesses and impeccable timing. What follows are photographs taken over the past several years on trips to the Bahamas and Isla Guadalupe, an island off the coast of the Baja California peninsula in Mexico. (Photo by Todd Bretl)

We place too much value into something as elusive as time. This is the lesson that Arina Pozdnyak, the creator of Perpetual Calendar, is trying to teach us. Days fly by, and even months are mere speckles of sand in an hourglass of eternity. People do not realize that the time given to us by fate cannot be measured using months or even years. It is measured using emotions and impressions. If a person lives to be 150 years old without experiencing any emotions, he might as well have lived one day, for all it’s worth. On the other hand, a person who lived an exciting, fulfilling life, read countless books and cherished every moment that he had, is actually the one who lived a longer life, even if in reality his flame was snuffed out much too soon. (Photo by Arina Pozdnyak)

The couple freedivers Eusebio and Christina Saeyns de Santamaria, known as «One ocean One breath», exploring the pond around the world, plunging into the water deep down in one breath.

Challenger Deep Submersible is shown for the first time at the Virgin Group Media Announcement by the President & CEO of Virgin Airlines Sir Richard Branson at the Newport Harbor Yacht Club on April 5, 2011 in Balboa, California. (Photo by John M. Heller/Getty Images)

Praia du Forte, Bahia. “This was the lead picture for a National Geographic story on Bahia, because it was both mysterious as well as a “geography” picture showing where the slaves arrived from Nigeria. Beach pictures seem like they should be easy to take, but for me they are actually quite difficult. Too easy to fall into cliche. When I saw the kid coming on the horse, I quickly ran to see if I could make something with a woman in a bikini that was not a bikini shot”. (Photo by David Alan Harvey/The Guardian)

“Serengeti National Park encompasses 5,700 square miles of grassy plains and woodlands near the northern border of Tanzania, and is home to more than 3,500 lions grouped into a couple dozen prides. Photographer Nick Nichols and videographer Nathan Williamson made several extended trips to the Serengeti between July 2011 and January 2013, determined to break new visual ground in their coverage of the Serengeti Lions”. Photo: Cubs of the Simba East pride: too young to kill but old enough to crave meat. Adult females, and sometimes males, do the hunting. Zebras and wildebeests rank high as chosen prey in the rainy season. (Photo by Michael Nichols/National Geographic via The Atlantic)

People will spout about impermanence of digital records, but books are really fragile, too. Alexis Arnold from San Francisco wanted to illustrate that with her project The Crystallized Book: collecting books and growing Borax crystals on them. Books range from literature classics to magazines, and there’s even a mysterious and arcane tome called “Linux: The Complete Manual”.

These snaps show a series of crafty critters camouflaged out of view. Many adventurous animals love to stand out from a crowd, but there are times when they need to blend in a bit more too. Photo: Tall story – can you spot the giraffe? (Photo by Caters News)