An African Penguin holds a Valentine's Day card at the California Academy of Sciences on February 13, 2013 in San Francisco, California. In honor of Valentine's Day, the colony of African Penguins at the California Academy of Sciences received heart-shaped red valentines with hand written messages from Academy visitors. (Photo by Justin Sullivan)

Cassie Douthwaite (L) and Stuart Abercrombie from Preston pose for a portrait in Brighton, southern England February 16, 2013. Brighton hosts “The Brighton Tattoo Convention” this weekend, an annual two-day gathering which attracts visitors, performers and tattoo artists from around the world. Photograph taken February 16, 2013. (Photo by Toby Melville/Reuters)

Freshly shorn alpacas are pictured on a meadow in the village of Winklarn near Regensburg April 22, 2013. The alpacas are always shorn in spring, to make the animals more comfortable for the summer months and to collect the expensive and well known alpaca wool. (Photo by Michaela Rehle/Reuters)

Long-tailed mayflies (Palingenia longicauda) at Tisza river near Tiszainoka 135km (84 miles) southeast of Budapest, June 23, 2013. Millions of these short-lived mayflies engage in a frantic rush to mate and reproduce before they perish in just a few hours during “Tiszaviragzas” or Tisza blooming season from late spring to early summer every year. (Photo by Laszlo Balogh/Reuters)

People dressed in Samurai costume and helmet march during the annual Himeji Castle Festival on August 3, 2013 in Himeji, Japan. The parade of Castle Queens is part of the traditional matsuri festival around the UNESCO world heritage Himeji Castle. (Photo by Buddhika Weerasinghe)

A mushroom cloud dwarfs a row of skyscrapers in what looks like a devastating nuclear bomb detonation. But thankfully this is just a spectacular weather-front blasting in from the tempestuous Rocky Mountains near Denver, Colorado, USA. The unbelievable shot is just one of many of the city's skyline taken by photographer Greg Thow. The 49-year-old has also captured equally stunning shots of lightning blasts and arching rainbows – all from the comfort of his balcony. (Photo by Greg Thow/Barcroft Media)

“Guns have a massive amount of power associated with them. They are designed to kill. We decided to photograph portraits of them in a similar way you might photograph a powerful person. Like powerful people, pistols have this “perfect” quality that we wanted to explore. As we started shooting them, we could see flaws in their design. Metal burring around the barrels, scratches in the metal. This imperfection and detail were very interesting to us; connecting us back to these images as portraits”. – Peter Andrew. (Photo by Peter Andrew/Simon Duffy/Derek Blais)

Papai Simon Ole Mamai of the Maasai Cricket Warriors team from Kenya runs during a match against English team “The Shed” during “The Last Man Stands” cricket tournament at Dulwich sports ground in South London September 1, 2013. (Photo by Philip Brown/Reuters)