Mahouts return home with their elephants carrying grass to feed them on the eve of the rhino census in Kaziranga National Park in Assam state, India, 24 March 2015. Kaziranga will be closed to visitors for the next two days for a census of the rhinos commencing 25 March, in a previous census in 2013 in the park the population of the Indian rhinos was 2329. (Photo by EPA/Stringer)

Two robotic legged squad support system (LS3) machines by the Defense Advanced Research Project Agency follow a technician during a demonstration at Joint Base Myer-Henderson Hall, Virginia, on September 10, 2012. (U.S. Marine Corps photo by Sgt. Mallory S. VanderSchans via The Atlantic)

Small transportation boats, known as bumboats, leave trails of light as they travel across Marina Bay past the skyline of Singapore in this photo taken in 2004. Singapore holds a Jubilee weekend from 7 to 10 August to celebrate the 50th anniversary of its independence. Fifty years ago, hundreds of small boats lined the Singapore river in the city centre. Today, most small boats are gone, except a handful of neon-lit tourist ferries. Maritime trade is still the backbone of the city-state but after decades of rapid growth Singapore, which at less than half the size of London is among the world’s most densely populated nations, is also a popular tourist destination and a thriving global financial hub. (Photo by Edgar Su/Reuters)

“Show Time”. It's a normal behavior of mantis. They're doing defence. When they're afraid of; raising their arms and spreading their wings. They looks like smiling dancer. Photo location: Nicosia, Cyprus. (Photo and caption by Hasan Baglar/National Geographic Photo Contest)

A copper plated Oscar statuette is run through a series of chemical baths at Epner Technology in the Brooklyn borough of New York, Tuesday, January 17, 2017. Every Oscar fist-pumped or tearfully cradled by Academy Award winners is first cast, buffed and fussed over by people far from Hollywood who have spent the last several months making 60 identical gold Oscars for the Feb. 26th awards. (Photo by Seth Wenig/AP Photo)

Festival goers pose for photographers on the third day of Glastonbury Festival at Worthy Farm, Somerset, England, Friday, June 28, 2019. Temperatures are expected to soar over the weekend as a heatwave hits parts of Europe, while the festival runs for five days and is one of the largest events of its kind in the world. (Photo by Joel C. Ryan/Invision/AP Photo)

Tattoo artists work on clients during the second International Tattoo Festival in Sochi, Russia, April 23, 2016. (Photo by Kazbek Basayev/Reuters)