Female members of police commando march during a ceremony on International Women's Day, at the police headquarters in Islamabad, Pakistan March 8, 2018. (Photo by Faisal Mahmood/Reuters)

In this April 14, 2018 photo, National Ballet of Cuba dancer Daniela Gomez Perez stands on point as she poses outside the Capitol in Havana, Cuba. Gomez, who says Cubans love dancing, trusts the next generation of leaders will continue such traditions and that art will continue to be the engine of Cuban society. Gomez said she is proud to represent Cuba during a dance trip in May to Washington, Tampa and Chicago, and that the Cuban state has always supported dance. (Photo by Ramon Espinosa/AP Photo)

Iraqi firefighters try to stop the fire of burning oil wells in Kirkuk, northern Iraq, 02 June 2016. Two Khabbaz oil field wells in Kirkuk Province, northern Iraq, exploded by suspected insurgents, a security official said. (Photo by EPA/Stringer)

A man rides a horse while others swim on the beach of Gaza City, Friday, August 3, 2018. (Photo by Khalil Hamra/AP Photo)

Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)

An artist dressed as demon King Ravana reacts as he participates in Vijaya Dashmi, or Dussehra festival celebrations in Chandigarh, India October 19, 2018. (Photo by Ajay Verma/Reuters)

Former “The Hills” star Audrina Patridge and her on again, off again boyfriend Corey Bohan get into a huge fight after attending Matthew Morrison's Halloween Party at Hyde Nightclub in West Hollywood, California on October 25, 2014. Audrina and Corey, who recently split up this past summer, seemed to be in great spirits before the party started but afterwards it was a whole different story! The not so happy couple argued on a bench and at one point a visibly upset Audrina sat on the sidewalk crying! (Photo by FameFlynet)

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)