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)

A Vietnamese woman collects dried incense sticks at a courtyard in Quang Phu Cau village on the outskirts of Hanoi on January 9, 2020 ahead of the upcoming Lunar New Year celebrations, referred to in Vietnam as Tet. (Photo by Manan Vatsyayana/AFP Photo)

Taylor Swift fans wait for the doors of Nilton Santos Olympic stadium to open for her Eras Tour concert amid a heat wave in Rio de Janeiro, Brazil, Saturday, November 18, 2023. A 23-year-old Taylor Swift fan died at the singer's Eras Tour concert in Rio de Janeiro Friday night, according to a statement from the show's organizers in Brazil. (Photo by Silvia Izquierdo/AP Photo)

A view of St Thomas Becket church during the morning frost, in Fairfield, Kent, England, Thursday, January 6, 2022, following freezing overnight temperatures. (Photo by Gareth Fuller/PA Wire via AP Photo)

Iraqi women practice at the sports club in Diwaniya, Iraq on November 10, 2018. On the blue mats of the al-Rafideen Club in the conservative city of Diwaniya, some 180 km (110 miles) south of Baghdad, some 30 female wrestlers, some still wearing headscarves, train three times a week. When a big competition comes up, they train every day. (Photo by Alaa Al-Marjani/Reuters)

A newborn grey seal pup is tended by its mother at Donna Nook, a nature reserve on the county’s coastline managed by Lincolnshire Wildlife Trust in Lincolnshire, UK on November 23, 2015. (Photo by David Tipling/Rex Shutterstock)

The secretive indri (Indri indri) of Madagascar, the largest living lemur. It is also critically endangered and highly evolutionarily distinct with no close relatives, which makes its branch one of most precarious on the mammal evolutionary tree. In the likely event that the indri goes extinct, we will lose 19m years of unique evolutionary history from the mammal tree of life. (Photo by Pierre-Yves Babelon/Aarhus University)

(From front to back) Carson, Rosie and Charlie Surfs Up compete during the World Dog Surfing Championships in Pacifica, California, on August 5, 2023. The event helps local charities raise money by sponsoring a contestant or a team, with a portion of the proceeds going to dog, environmental, and surfing nonprofit organizations. (Photo by Josh Edelson/AFP Photo)