A two-horse team street cleaner, with sprayer, squeegee, and roller at rear. New York, between ca. 1910 and ca. 1915. (Photo by NYC Municipal Archives)

Dustin Murley (L) and Jessey Sisson race on their ostriches during the annual Ostrich Festival in Chandler, Arizona March 10, 2013. (Photo by Joshua Lott/Reuters)

Billions of newly hatched locusts are spreading throughout Israel's South. The young locusts identified in the Negev Desert area are the offspring of locust swarms that entered Israel from Egypt in March. (Photo by Eliahu Hershkovitz/Haaretz)

Construction work on the tower began in November 2008. Upon its completion this year the building will stand approximately 632 meters (2,073 ft.) high and will have 121 stories. It is expected to open to the public in 2015. (Photo by Rex Features)

A craftsman works on making human anatomy mannequins on April 23, 2014 in Depok, West Java, Indonesia. The mannequins are made from fiberglass and will be used in schools, hospitals and laboratories. (Photo by Nurcholis Anhari Lubis/Getty Images)

A country music fan cools off in the wind on the second day of the Stagecoach country music festival in Indio, California April 26, 2014. (Photo by Mike Blake/Reuters)

Colored Pencil and Origami Landscapes: Ivanova's version of the popular Snake game features a chain-link origami snake chasing a butterfly. (Photo by Victoria Ivanova)

A female member of the Ahbab Al-Mustafa Battalion holds a gun as she undergoes military training in Aleppo's Salaheddine district, June 24, 2013. (Photo by Muzaffar Salman/Reuters)