A military police officer aims his gun to a demonstrator during a protest in Brasilia, Brazil, Tuesday, April 7, 2015. The officer had picked up a bottle that was thrown towards them but did not fire his gun and backed away. Thousands of workers have staged rallies in 12 cities across Brazil to protest against a proposed law that would allow companies to outsource their labor force. (Photo by Eraldo Peres/AP Photo)

Workers carry baskets of hand-picked tea leaves at the Makaibari Tea Estate in Kurseong, West Bengal, India, on Monday, September 8, 2014. The 155-year-old Makaibari Tea Estate recently sold it's Darjeeling tea, named Silver Tips Imperial, for $1,850 a kilo to buyers from the U.K., the U.S. and Japan, becoming the most expensive Indian tea ever sold. (Photo by Sanjit Das/Bloomberg)

These unique photos capture the moment a boy has his teeth picked clean by amazing underwater shrimp. These fascinating creatures spend their lives diving inside the mouths of fish to remove the parasites that lurk there. Russell Laman imitated the behaviour of the surrounding fish swarm to entice the cleaner shrimp into his mouth whilst snorkelling with his father Tim Laman in Bali, Indonesia. The 13-year-old queued with the waiting fish and then opened his mouth when the shrimps came near. (Photo by Tim Laman/Caters News)

The anthropomorphic robot named hitchBOT sits on the shoulder of Highway 102 to begin its 6000 kilometer cross country journey outside of Halifax, Nova Scotia, July 27, 2014. The hitch hiking robot is part of a social experiment to see if drivers will pick up and drop off the robot in one piece to an art gallery in Victoria, British Columbia. (Photo by Paul Darrow/Reuters)

A miner with a donkey makes his way through the low and narrow tunnel leading out of a coal mine in Choa Saidan Shah in Punjab province, April 29, 2014. Workers at this mine in Choa Saidan Shah dig coal with pick axes, break it up and load it onto donkeys to be transported to the surface. Employed by private contractors, a team of four workers can dig about a ton of coal a day, for which they earn around $10 to be split between them. The coalmine is in the heart of Punjab, Pakistan's most populous and richest province, but the labourers mostly come from the poorer neighbouring region of Khyber Pakhtunkhwa. (Photo by Sara Farid/Reuters)

In this Sunday, November 16, 2014 photo, Nepalese women pick tea at a tea garden of Kanyam in Illam district, around 500 kilometers (310 miles) from Katmandu, Nepal. Illam is a hilly district of tea gardens and estates in eastern Nepal's Himalayan region with one of its largest and most productive tea estate being Kanyam estates. The district produces orthodox tea, hand-processed or machine rolled, which is generally exported to international markets, specially Europe and the United States. Most of the tea pickers here are paid 186 Nepalese Rupees (US $ 2) for 8 hours of work everyday. (Photo by Niranjan Shrestha/AP Photo)

A pile of destroyed cars of teachers sits outside Briarwood elementary school in Oklahoma City, Oklahoma May 22, 2013. Rescue workers with sniffer dogs picked through the ruins on Wednesday to ensure no survivors remained buried after a deadly tornado left thousands homeless and trying to salvage what was left of their belongings. Curvature of horizon in the photo is due to an ultra-wide angle lens. (Photo by Rick Wilking/Reuters)

Protesters run for cover after riot police fired tear gas towards the bridge they were climbing down to the road below, to escape from Hong Kong Polytechnic University campus and from police, in Hung Hom district in Hong Kong on November 18, 2019. Dozens of Hong Kong protesters escaped a besieged university campus on November 18 by lowering themselves on a rope from a footbridge to a highway, AFP video showed. Once on the road they were seen being picked up by waiting motorcyclists. (Photo by Anthony Wallace/AFP Photo)