A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

The Spanking. (Photo by Vika Valter/Getty Images)

“As a photographer, peregrinator and naturalist, I have been searching for the ultimate unworldly world. I've always been drawn to unusual travel destinations. For me, to lose myself in a different culture is a great way to find balance in my life...”. – Li Xinzhao. (Photo by Li Xinzhao)

An opposition activist clashes with the police during a march against Venezuelan President Nicolas Maduro held on May Day, in Caracas on May 1, 2017. Security forces in riot vans blocked off central Caracas Monday as Venezuela braced for pro- and anti- government May Day protests one month after a wave of deadly political unrest erupted. (Photo by Federico Parra/AFP Photo)

Soap Bubble Structures by Kym Cox. Bubbles optimise space and minimise their surface area for a given volume of air. This phenomenon makes them a useful tool in many areas of research, in particular, materials science and “packing” – how things fit together. Bubble walls drain under gravity, thin at the top, thick at the bottom, which interferes with travelling lightwaves to create bands of colour. Black spots show the wall is too thin for interference colours, indicating the bubble is about to burst. (Photo by Kym Cox/2019 Science Photographer of the Year/RPS)

Heesco, Windsor. Born and raised in Mongolia and now living and working in Melbourne, Heesco is well known for his skill in rendering photo-realistic portraits. They speak to the viewer in a way that the subtext is enjoyable to decipher. Just what is the Blue Lady’s message? The sunglasses might mask the confronting gaze but her body language fills in the gaps. Heesco’s characters often wear traditional jewellery and clothing that remind us of his Mongolian cultural heritage. (Photo by Lou Chamberlin/The Guardian)

This 2014 series Shanghai Tian Wa saw Chinese photographer Liu Tao train his lens on two distinct districts in Shanghai. Here: “Shanghai Tian Wai №26, 2014”. (Photo by Liu Tao/The Guardian)

Brazilian Tapir Tique is treated to a nice cold shower by the zoo keeper at Taronga Zoo on January 8, 2013 in Sydney, Australia. Temperatures are expected to reach as high as 43 degrees around Sydney today. (Photo by Marianna Massey)