In this undated photo made available by journal Nature on January 15, 2014, a northern bald ibis (Geronticus eremita) flies in Tuscany, Italy. A new study released Wednesday, January 15, 2014 says the birds choreograph the flapping of their wings, getting a boost from an updraft of air in the wake of the flapping wings by flying behind the first bird and off to the side. When a flock of birds take advantage of these aerodynamics, they form a V. (Photo by Markus Unsöld/AP Photo)

Members of security forces secure Tahrir Square in Cairo, Egypt, November 11, 2016. Egypt imposed a big security clampdown in its cities on Friday as mass demonstrations called to protest against austerity measures failed to take place. Riot police and armored vehicles filled the otherwise empty streets of central Cairo, but most people stayed at home. (Photo by Mohamed Abd El Ghany/Reuters)

In advance of Fleet Week performances, U.S. Navy Blue Angels fly above San Francisco with Team Oracle aerobatics pilots Sean D. Tucker and Jessy Panzer on Thursday, October 10, 2019. (Photo by Noah Berger/AP Photo)

In this Sunday, March 5, 2017 photo, hospitality staff pose for photos on Tiananmen Square during the National People's Congress held at the Great Hall of the People in Beijing. (Photo by Andy Wong/AP Photo)

In this Friday, January 7, 2011 photo, people carry baskets of coal scavenged illegally at an open-cast mine in the village of Bokapahari in the eastern Indian state of Jharkhand where a community of coal scavengers live and work. The world's biggest coal users – China, the United States and India – have boosted coal mining in 2017, in an abrupt departure from last year's record global decline for the heavily polluting fuel and a setback to efforts to rein in climate change emissions. (Photo by Kevin Frayer/AP Photo)

A model presents a creation from the Liu Bolin Debut collection during New York Fashion Week in the Manhattan borough of New York City, U.S., September 10, 2017. (Photo by Amr Alfiky/Reuters)

Ballerinas Kennedy George, 14, and Ava Holloway, 14, pose in front of a monument of Confederate general Robert E. Lee after Virginia Governor Ralph Northam ordered its removal after widespread civil unrest following the death in Minneapolis police custody of George Floyd, in Richmond, Virginia, U.S. June 5, 2020. (Photo by Julia Rendleman/Reuters)

Parade-goers walk in the annual West Indian Day Parade on September 02, 2019 in the Brooklyn borough of New York City. The annual celebration of Caribbean culture is one of the largest of its kind and features dozens of floats and costumed participants that make their way down Flatbush Avenue. (Photo by Yana Paskova/Getty Images)