Street vendors carry chickens for sale at Kawran Bazar in Dhaka, Bangladesh January 25, 2017. (Photo by Mohammad Ponir Hossain/Reuters)

A woman receives a bouquet made of vegetables and flowers, priced at 238RMB, from a delivery staff of a florist outside an office building on Valentine's Day in Beijing, China, February 14, 2017. (Photo by Jason Lee/Reuters)

Revelers dance at the Old Settler's Music Festival in Driftwood, Texas, U.S. on April 22, 2017. (Photo by Mohammad Khursheed/Reuters)

Sri Lankan participants control their bulls during a traditional cart race to mark the Sri Lanka National New Year in Homagama near Colombo on April 23, 2017. The new year marked by both the majority Sinhalese and minority Tamil population fell on April 14. (Photo by Lakruwan Wanniarachchi/AFP Photo)

Television personality Farrah Abraham (C) enjoys adult entertainment as she hosts the VIP Back Door Key party at the Crazy Horse III Gentlemen's Club on August 4, 2017 in Las Vegas, Nevada. The newly launched VIP membership program offers patrons exclusive entrance to the club through the back door. (Photo by Bryan Steffy/WireImage)

A mother takes a selfie while breastfeeding her baby at the “Hakab Na 2018”, an event held in celebration of National Breastfeeding Awareness Month at the SMX Convention Center in Pasay City, Philippines on Sunday, August 5, 2018. Now on its sixth year, the event is a gathering of families, lactation experts, peer counselors and breastfeeding advocacy supporters and was aimed at promoting the importance of providing support to breastfeeding mothers. (Photo by Avito C. Dalan/PNA 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)

A sandstorm hits the city of Zhangye in Gansu province, China on November 27, 2018. (Photo by Reuters/China Stringer Network)