The tusk of a woolly mammoth that lived some 18,000 years ago, from which researchers sequenced the extinct mammal's entire genome, is seen in northeastern Siberia in this photo from 2015. (Photo by Love Dalen/Handout via Reuters)

Forrest Walker, “Police Walk”. Walker describes this shot, taken in 2015 at the last officially permitted Pride parade in Istanbul, as a tense and surreal experience. His focus is on a woman walking calmly in front of a line of riot police, her attitude part defiance and part performance. (Photo by Forrest Walker/All About Photo awards 2025 via The Guardian)

A man wearing a mask and dressed in a clown costume rides an electric tricycle while carrying a container in the shape of a rubber duck amid heavy smog in Beijing, China, December 29, 2015. (Photo by Jason Lee/Reuters)

People line up to pay inside a Makro supermarket in Caracas, January 9, 2015. Venezuela's socialist government decreed an “economic emergency” on Friday that will expand its powers and published the first data in a year that shows the depth of a recession fueled by low oil prices and a sputtering state-led model. (Photo by Jorge Silva/Reuters)

Lioness and hyena posture to one another, in Masai Mara, Kenya, August 2015. A photographer captured one of the oldest rivalries in the animal kingdom as a pair of lions went head to head with a pack of hungry hyenas. (Photo by Ingo Gerlach/Barcroft Images)

Swimmers in fancy dress splash as they participate in the New Year's Day Loony Dook swim at South Queensferry, Scotland January 1, 2015. (Photo by Russell Cheyne/Reuters)

A boy fires confetti poppers as he participates in a procession to mark Eid-e-Milad-ul-Nabi, the birthday celebration of Prophet Mohammad, in Mumbai January 4, 2015. (Photo by Danish Siddiqui/Reuters)

Ana Ivanovic of Serbia plays a backhand return to Maria Sharapova of Russia during their women's singles final match at the Brisbane International tennis tournament in Brisbane, January 10, 2015. (Photo by Jason Reed/Reuters)