View of colourful rock formations at the Zhangye Danxia Landform Geological Park in Gansu Province, China. The Zhangye Danxia Landform Geological Park is 40km from Zhangye city. The park spans more than 400 square kilometers in Gansu. The unusual terrain is the result of red sandstone and mineral deposits carved over the years by natural forces. (Photo by ImagineChina/The Grosby Group)

Winner of the National Park Foundation's photo contest; Honorable Mention: Fan Favorite. Grand Canyon National Park, Arizona. Three friends enjoy sunrise over the Grand Canyon. (Photo by Peter Blanchard)

A child dressed as a cat takes part in the Children's Halloween day parade at Washington Square Park in the Manhattan borough of New York October 31, 2015. (Photo by Carlo Allegri/Reuters)

Two Red Deer stags stand in the early morning mist in Richmond Park on October 15, 2011 in London, England. Autumn sees the start of the “Rutting” season where the large Red Deer stags can be heard roaring and barking in an attempt to attract females known as bucks. The larger males can also be seen clashing antlers with rival males. (Photo by Dan Kitwood/Getty Images)

A zebra walks through the recently flooded Safari Park located at Safari World November 2, 2011 in Bangkok, Thailand. (Photo by Paula Bronstein /Getty Images)

Cole Yeoman steps over a large crack along River Road, Avonside on February 25, 2011 in Christchurch, New Zealand. The death toll has risen to 113 and the hope for finding survivors is fading as rescuers search through debris for over 200 still missing following a 6.3 magnitude earthquake that struck Christchurch on Tuesday. The quake, which was an aftershock of a 7.1 magnitude quake that struck the South Island city on September 4, 2010, has seen damage and fatalities far exceeding those of the original. (Photo by Martin Hunter/Getty Images). CHRISTCHURCH, NEW ZEALAND – FEBRUARY 25

Imogen Bankier of Scotland (L) and Chris Adcock of England in action during their round one mixed doubles match in the Yonex All England Badminton Open Championship on March 9, 2011 in Birmingham, England.