Alfred the frog looks almost as scary as the pumpkin he is perched on at London Zoo 26 October 2011. Keepers at the zoo have joined in the Halloween tradition by supplying pumpkin lunches to some of their animals, including the giant waxy monkey frog. However Alfred is not quite the giant figure his species name suggests – he actually measures up at around 4 inches (10 centimeters). (Photo by EPA/Zoological Society of London)

Engineer Thomas Dwyer stands with the new Bionic Exoskeleton next to Amanda Boxtel during its launch at the Excel centre on October 21, 2011 in London, England. The bionic device developed by Ekso Bionics is a wearable, battery-powered, robotic exoskeleton, designed to aid wheelchair users and those who have suffered from spinal chord injuries to stand and walk. (Photo by Dan Kitwood/Getty Images)

A girl holds onto a pole as as she stands in floodwaters flowing from the swollen Bagmati River caused by heavy rainfall in Kathmandu, Nepal August 17, 2015. (Photo by Navesh Chitrakar/Reuters)

Pro-government fighters stand next to a tank destroyed during recent fighting in Yemen's southwestern city of Taiz March 14, 2016. (Photo by Anees Mahyoub/Reuters)

A woman dressed as a character from the computer game “World of Warcraft” stands in a forest near the village of Sosnova, Czech Republic, April 30, 2016. (Photo by David W. Cerny/Reuters)

A participant covered in coloured powder gestures as she stands near a Syrian army soldier during “I Love Damascus” marathon at Umayyad Square in Damascus, Syria October 7, 2016. (Photo by Omar Sanadiki/Reuters)

A policeman kick in the door of a residence next to the Black Panther headquarters in New Orleans as they moved in following a shootout, September 15, 1970. Other heavily armed policemen stand at ready. (Photo by Jack Thornell/AP Photo)