A chimpanzee relaxes in the shade at the Safari Park as the popular attraction prepares for the upcoming Jewish festival of Pesach (Passover) on April 14, 2008 in Ramat Gan near Tel Aviv, Israel. (Photo by David Silverman/Getty Images)

People ride bicycles in Halloween costumes during “Bike Kill 13” in the Brooklyn borough of New York City, October 29, 2016. “Bike Kill” is an annual gathering of builders and riders of home-made bicycles that culminates in a tall bike jousting competition. (Photo by Stephanie Keith/Reuters)

Nepalese Hindu devotees take part in a bathing ritual on the last day of the month-long Swasthani Festival in the Hanumante River at Bhaktapur on the outskirts of Kathmandu on February 22, 2016. Devotees mark the Swasthani Festival with fasting, and with women in particular undertaking rituals in the hope of a prosperous life for her family and conjugal happiness. (Photo by Prakash Mathema/AFP Photo)

A fighter of Libyan forces allied with the U.N.-backed government runs for cover during a battle with Islamic State fighters in Sirte, Libya, July 31, 2016. (Photo by Goran Tomasevic/Reuters)

Two wrestling camels fight at the Pamucak arena during the Selcuk-Efes Camel Wrestling Festival in the town of Selcuk, near the western Turkish coastal city of Izmir January 18, 2015. Thousands of enthusiasts visit the city through the weekend to watch wrestling between Dromedary camels, who are bred specially for the annual Selcuk-Efes Camel Wrestling Festival. (Photo by Osman Orsal/Reuters)

Hindu devotees, their bodies pierced with lemon and paladai, or bowl with a spout mainly used to feed milk to infants, wait to participate in a procession to mark Shivratri, or the night of Shiva, in Chennai, India, Wednesday, February 18, 2015. Such processions are held as an offering and show of devotion by devotees on the day dedicated to the worship of Lord Shiva, the Hindu god of destruction. (Photo by Arun Sankar K./AP Photo)

Five hundred replicas of the Stormtrooper characters from "Star Wars" are placed on the steps at the Juyongguan section of the Great Wall of China during a promotional event for "Star Wars: The Force Awakens" film, on the outskirts of Beijing, China, October 20, 2015. (Photo by Jason Lee/Reuters)

Taronga Zoo's elephant baby, as yet unnamed, is seen at Taronga Zoo on March 12, 2010 in Sydney, Australia. The Asian Elephant calf has continued to make progress following a protracted labour that spanned six days. The calf was originally believed to have died in the womb during labour but surprised veterinarians and zoo staff with an unexpected delivery early Wednesday morning. (Photo by Bobby-Jo Vial/Taronga Zoo via Getty Images)