Nazi dictator Adolf Hitler greets supporters at a May Day gathering in the Olympic Stadium, Berlin. (Photo by Keystone). 1st May 1938

Western lowland gorilla Kijivu holds her newborn baby at the Prague Zoo in the Czech Republic. (Photo by Isifa/Getty Images)

Employees wear "No-Face" masks during working hours at a service company in Handan, Hebei Province of China. As a service company, staff must smile to customers every day. On “No-Face Day”, staff wore masks to hide their facial expressions and allow them to relax. No-Face is a character in the 2001 animated movie “Spirited Away”, a silent masked creature who has no facial expressions.

A Hindu devotee performs a ritual on Bagmati River during Kuse Aunse (Father's Day) at Gokarna Temple in Kathmandu, Nepal September 13, 2015. Hindus all over the country, whose fathers have passed away, come to the temple for worship, holy dips, and to present offerings on this occasion. (Photo by Navesh Chitrakar/Reuters)

Troops of the Interior Ministry take part in a parade during a ceremony marking the Iraqi Police Day at a police academy in Baghdad January 9, 2016. (Photo by Khalid al Mousily/Reuters)

Faithful jump into the waters of Fasilides Bath as part of a ceremony in which the waters are blessed by the priest of Ethiopian Orthodox Tewahedo church during the second day of Timket in Gondar, Ethiopia, January 20, 2016. “Timket”, the greatest Ethiopian festival of the year is to commemorate Jesus Christ's baptism in the Jordan River by John the Baptist. (Photo by Tiksa Negeri/Reuters)

An Indian Army soldier marches next to a tableau during the Republic Day parade in New Delhi, India, January 26, 2016. India celebrated its Republic Day Tuesday, highlighted by a march by different branches of the military as well as a display of arms and missiles. (Photo by Adnan Abidi/Reuters)