Two Herens cows lock horns during the qualification round of the annual “Battle of the Queens” cow fight finals in Aproz, in the western Alpine canton of Valais May 5, 2013. Each year when taken to the alpine pastures, the cows test their strength and fight for the herd's leadership. The competition continues until a new queen has forced all the other cows to retreat. (Photo by Valentin Flauraud/Reuters)

A fox runs out onto the pitch before the start of the second half. Celtic League 2012/13, Round 19, Leinster v Ulster, RDS, Ballsbridge, Dublin, March 30, 2013. (Photo by Paul Mohan)

A British fan waits to enter the Malmo arena ahead of the finals of the 2013 Eurovision Song Contest on May 18, 2013. (Photo by John MacDougall/AFP Photo)

Muslim women light candles during the “EarthHour” in Jakarta, Indonesia, on March 23, 2013. Hundreds of people observed the global event that encourages people to turn off their lights for 60 minutes. (Photo by Dita Alangkara/Associated Press)

Final match Soccer Humanoid Kid Size between DARwIn vs. AUTMan at the World Championship finals of RoboCup 2013 in Eindhoven (NL). (Photo by Bart van Overbeeke)

Runners gather at the start line for the annual “Santa Speedo Run”, a charity race through the streets of the Back Bay neighborhood of Boston. (Photo by Gretchen Ertl/Reuters)

Poland's Maria Andrejczyk competes in the women's javelin throw final of the athletics event at the Paris 2024 Olympic Games at Stade de France in Saint-Denis, north of Paris, on August 10, 2024. (Photo by Dylan Martinez/Reuters)

A breeder puts a giant panda cub into a crib at Chengdu Research Base of Giant Panda Breeding in Chengdu, Sichuan province, September 23, 2013. Fourteen new joiners to the 128-giant-panda-family at the base were shown to the public on Monday, according to local media. (Photo by Reuters/China Daily)