The double compound eyes of a male St. Mark's fly (Bibio marci), submitted by Dr. David Maitland from Feltwell, UK. (Dr. David Maitland)

Riot Police form a cordon as a Police car burns on the opening day of the European Central Bank (ECB) in Frankfurt am Main, western Germany, on March 18, 2015. Supporters of the so-called Blockupy alliance consisting of social movements, activists, workers, trade unions and parties are expected to stage large protests against austerity and the authority of the European Central Bank when the bank's new headquarters officially will be on March 18, 2015. (Photo by Odd Andersen/AFP Photo)

A model presents a creation by Italian designer Donatella Versace as part of her Haute Couture Fall/Winter 2016/2017 fashion show for Atelier Versace in Paris January 24, 2016. (Photo by Gonzalo Fuentes/Reuters)

Biologist Kelly Martin records her measurements of Electra, a 5 1/2 foot leatherback turtle nesting on the beach behind the Seminole Golf Club course in Juno Beach. Martin uses a red light which is invisible to turtles. (Photo by Greg Lovett/The Palm Beach Post)

A female brown bear with cubs fishing on Lake Kronotskoye as part of the South Kamchatka, Russia on Sanctuary, August 13, 2017. (Photo by TASS/Barcroft Images)

British fashion model Twiggy plays around on the bumper cars at the Bertram Mills Circus in London, England on January 10, 1967. (Photo by AP Photo)

People take part in a snowball fight in front of the Colosseum covered by snow during a snowfall in Rome, Italy, 26 February 2018. Media reports on 26 February state that extreme cold weather is forecast to hit many parts of Europe with temperatures plummeting to a possible ten year low. (Photo by Angelo Carconi/EPA/EFE)

A walker has left a handprint on a snow- covered tree trunk on Grosser Feldberg mountain in the Taunus mountain range, Germany, 16 January 2017. (Photo by Frank Rumpenhorst/DPA)