Tao Xiangli gets out of his homemade submarine after operating it in a lake on the outskirts of Beijing September 3, 2009. Amateur inventor Tao, 34, made a fully functional submarine, which has a periscope, depth control tanks, electric motors, manometer, and two propellers, from old oil barrels and tools which he bought at a second-hand market. He took 2 years to invent and test the submarine which costs 30,000 yuan ($4,385). (Photo by Christina Hu/Reuters)

Students receive a group punishment during a military-style close-order drill class at the Qide Education Center in Beijing February 19, 2014. The Qide Education Center is a military-style boot camp which offers treatment for internet addiction. As growing numbers of young people in China immerse themselves in the cyber world, spending hours playing games online, worried parents are increasingly turning to boot camps to crush addiction. Military-style boot camps, designed to wean young people off their addiction to the internet, number as many as 250 in China alone. (Photo by Kim Kyung-Hoon/Reuters)

In this handout provided by the National Aeronautics and Space Administration (NASA), SpaceX's Falcon 9 is moved to the launch pad prior to the rocket's Thales Alenia Space launch attempt on April 26, 2015 in Cape Canaveral, Florida. (Photo by NASA via Getty Images)

The model Gigi Hadid receives attention in Soho, New York, USA on June 27, 2017. (Photo by Broadimage/Rex Features/Shutterstock)

Cristine Angelie Garcia (C), 24, rides a jeepney on her way to work at a call centre for the midnight shift in Taguig city, Metro Manila, Philippines October 3, 2016. “Maybe there is another way where people do not need to die”, she said, adding she felt safer walking the streets at night. “I'm on Duterte's side. Maybe he's just misunderstood because he grew up on the streets”. (Photo by Ezra Acayan/Reuters)

Social activists working for the rights of sеx workers celebrate with colour powder during the International Sеx Workers' Rights Day in Kolkata on March 3, 2020. (Photo by Dibyangshu Sarkar/AFP Photo)

Tourists wear protective masks in Sanur, Bali, Indonesia, 15 March 2020. Indonesia has around 80 active cases of Covid-19. More than 70,000 people worldwide have recovered from coronavirus, nearly half of the total infections recorded since the outbreak began. (Photo by Made Nagi/EPA/EFE)

Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)