Team Strong Silvers member Ngai Hin Kwok, 66, works out as teammate Ng Siu Chi, 57, watches at a stadium in Singapore March 15, 2015. Team Strong Silvers, is a group of senior citizens who train in calisthenics. The trio trains individually at least three times a week, and meets up for joint calisthenics at least twice a month. (Photo by Edgar Su/Reuters)

A handout image released by the Taronga Zoo shows Veiled Chameleon hatchlings at Taronga Zoo in Sydney, Australia, 11 March 2015. Taronga has welcomed more than 20 baby chameleons, with the last of three clutches of eggs hatching this week. Veiled Chameleons, or Chamaeleo calyptratus, are native to Saudi Arabia and Yemen and can live up to five years. (Photo by EPA/Taronga Zoo)

A motorized three-wheeled taxi carrying Muslim students drives past the Starbucks cafe where Thursday's attack occurred in Jakarta, Indonesia, on Friday, January 15, 2016. A day after attackers detonated bombs and engaged in gunbattles with police in the central part of Indonesia's capital, Jakarta tried to get itself back on track. (Photo by Dita Alangkara/AP Photo)

Members of Japanese idol group Kamen Joshi (Masked Girls) pose for a photo after a rehearsal for a concert at their theatre in Tokyo's Akihabara district, Japan March 17, 2016. For countless girl and pop-idol bands in Japan, standing out from the crowd can be daunting, but one group – “Kamen Joshi” – seems to have found the answer by hiding behind masks. The Tokyo-based all female band has 18 members, split into three groups that perform across Japan and elsewhere in Asia. (Photo by Toru Hanai/Reuters)

In this April 20, 2017 photo, a woman is aided by fellow demonstrators after falling, overcome by tear gas, during anti-government protests in Caracas, Venezuela. Tens of thousands of protesters asking for the resignation of President Nicolas Maduro flooded the streets again, one day after three people were killed and hundreds arrested in the biggest anti-government demonstrations in years. (Photo by Ariana Cubillos/AP Photo)

Ja Kang Song, 71, and Ja Hyun Su, 72, dive for shellfish and are the main breadwinners for their families. In South Korea, 45% of the diving women of Jeju are over the age of 70. Routinely diving to depths of 20m and staying under for an average of two to three minutes, the pressure on the body takes its toll and, like many others, burst eardrums have left Ja Hyun Su deaf. Each season, between seven and 10 women die diving the waters around Jeju Island. (Photo by Andy W. Langton/Age International)

This August 15, 2016 photo shows two portraits Carolina, one of her holding a weapon while in her uniform for the Revolutionary Armed Forces of Colombia (FARC) 49th front, and in civilian clothing at a guerrilla camp in the southern jungle of Putumayo, Colombia. Carolina, 18, said she has spent three years in the FARC and would like to study engineering after demobilizing as part of a peace deal with Colombia's government. (Photo by Fernando Vergara/AP Photo)

Covered in prayer shawls, Ultra-Orthodox Jewish men participate in a blessing during the holiday of Sukkot, in front of the Western Wall, the holiest site where Jews can pray in Jerusalem's Old City, Wednesday, September 30, 2015. The Cohanim, believed to be descendants of priests who served God in the Jewish Temple before it was destroyed, perform a blessing ceremony of the Jewish people three times a year during the festivals of Passover, Shavuot and Sukkot. (Photo by Oded Balilty/AP Photo)