Visitors make snowmen beside a pool at a hot spring in Hangzhou, in China's eastern Zhejiang province on January 26, 2018. China's central and eastern regions have been hit by heavy snowfalls in recent days, causing disruptions to flight and train schedules. (Photo by AFP Photo/China Stringer Network)

South Vietnamese forces escort suspected Viet Cong officer Nguyen Van Lem (also known as Bay Lop) on a Saigon street February 1, 1968, early in the Tet Offensive. Moments later, Lem was executed by Gen. Nguyen Ngoc Loan, chief of the national police. (Photo by Eddie Adams/AP Photo)

An Indian Muslim worker applies colors on Kalavas (sacred threads) in Ajmer in the Indian state of Rajasthan on May 24, 2018. (Photo by Himanshu Sharma/AFP Photo)

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)

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)

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)

Workers carry a metal sheet at a dockyard in Dhaka, Bangladesh, December 5, 2018. (Photo by Mohammad Ponir Hossain/Reuters)

An unidentified fashion lover waits outside Chanel's Haute Couture fashion show during snowfall in Paris, Tuesday January 22, 2019. (Photo by Thibault Camus/AP Photo)