Behaviour winner; Courting Royals: two royal terns in courtship display by Kristian Bell. Another beautiful morning on a beautiful beach on the Gulf Coast of Florida seemed to prompt these two royal terns to commence an intricate courtship dance. The photograph was taken with a Canon 300mm lens and 2x extender. (Photo by Kristian Bell/Deakin University/Royal Society Publishing Photography Competition 2018)

“Sniff out the Appenzell Cheese”. Alexander Hunter, 30, of Greenwich, Conn., took this photo in Appenzell, Switzerland, in September 2014. (Photo by Alexander Hunter)

Harris & Ewing Inc. photographed people, events, and architecture, particularly in Washington, D.C., during the period 1905-1945. Photo: Tests of Curtiss Palne for Army, Single Control. Created by Harris & Ewing. Published in 1912.

Miss South Carolina Suzi Roberts competes in the swimsuit competition of the 97th Miss America Competition in Atlantic City, New Jersey U.S. September 10, 2017. (Photo by Mark Makela/Reuters)

A snowflake rests on black velvet after a snowfall in Knoxville on Tuesday, January 28, 2014. (Photo by Adam Lau/News Sentinel)