An upside-down pair of pants is seen atop a mound of snow, Wednesday, February 20, 2019, the result of yet another snow storm to hit Omaha, Neb. The latest winter storm dumped more snow on top of the existing snow, creating a problem of what to do with all the cleared snow. (Photo by Nati Harnik/AP Photo)

A member of an Egungun masquerade group, his identity obscured under his ornate costume in Ouidah, Benin on March 13, 2019. The exclusively male practitioners, found across Yoruba culture, use dance and spinning in the belief that they will summon the spirits of ancestors. (Photo by Massimo Rumi/Barcroft Images)

This Thursday, January 22, 2015 photo made with a long exposure shows the glow from a Noctiluca scintillans algal bloom along the seashore in Hong Kong. The luminescence, also called Sea Sparkle, is triggered by farm pollution that can be devastating to marine life and local fisheries, according to University of Georgia oceanographer Samantha Joye. Noctiluca itself does not produce neurotoxins like other similar organisms do. But its role as both prey and predator tends can eventually magnify the accumulation of toxins in the food chain, according to R. Eugene Turner at Louisiana State University. (Photo by Kin Cheung/AP Photo)

Soviet Army soldiers sit on their tanks in front of the Czechoslovak Radio station building in central Prague during the first day of Soviet-led invasion to then Czechoslovakia on August 21, 1968. (Photo by Libor Hajsky/Reuters)

The “Escape Velocity” moving sculpture by artist group Poetic Kinetics looms over Coachella festivalgoers on the Empire Polo Field, on the first day of the 2014 Coachella Music and Arts Festival in Indio, California, on April 11, 2014. (Photo by Chris Pizzello/Invision)

Yaroslav Segeda at the top of a high rise building in Kudrinskaya Square, Moscow, Russia. (Photo by Yaroslav Segeda/Caters News)

A red fox sits in front of a Eurofighter Typhoon combat jet on the grounds of the 2014 ILA Berlin Air Show, in Selchow near Schoenefeld, Germany, Thursday, May 15, 2014. The International Aviation and Aerospace Exhibition ILA will take place from May 20 until May 25, 2014. (Photo by Patrick Pleul/AP Photo/DPA)

“Two Brothers”. We found about 20 lions eating a buffalo. When the male leaved the group we anticipated him to take photos. It is 8AM, light is perfect and the position too. The lion stops and looks down from the hill, another lion is coming up, it stiffens, I think that will be a fight, i'm tense, the camera is OK, the shots previously made perfect. The two meet, looking directly into their eyes, they sniff, rub against their heads, the tension drops, they start walking with the same step as when they were puppies, they are two brothers. Photo location: Masai Mara, Kenya. (Photo and caption by Massimo Mei/National Geographic Photo Contest)