A dancer from the Trisha Brown Dance Company performs during “Roof Piece” above the High Line park June 9, 2011 in New York City. Roof Piece (1971) consists of nine dancers performing improvised movement signals to each other in a chain on various rooftops overlooking the city. This presentation marked the first full performance of the piece since 1973. (Photo by Mario Tama/Getty Images)

Children play at the Ryoji Ikeda exhibition “the transfinite” at the Park Avenue Armory on June 10, 2011 in New York City. The audio visual installation, which will close after tomorrow, features two back-two-back screens displaying a continual loop of sounds, fragments of numbers and strobe-lit patterns that echo the Japanese artist's interest in mathematics, the subconscious and the digital world. (Photo by Spencer Platt/Getty Images)

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 park worker holds a monitor lizard at Lumpini park in Bangkok, Thailand, September 20, 2016. More than 400 of the Monitor lizards in the park will be caught by Thai authorities to relocate the reptile to a wildlife breeding center in the effort to control the creature population in the public park after the monitor lizard disturbing and causing several minor accident of people who jogging and cycling at the Lumpini Park. (Photo by Athit Perawongmetha/Reuters)

This undated handout photo received from the Antarctic Ocean Alliance on October 28, 2016 shows a adelie penguin jumping onto the ice in the Ross Sea in Antarctica. The world's largest marine reserve aimed at protecting the pristine wilderness of Antarctica will be created after a “momentous” agreement was finally reached on October 28, 2016 with Russia dropping its long-held opposition. (Photo by John Weller/AFP Photo/Antarctic Ocean Alliance)

A tea ceremony master use the Hishaku made by bamboo and makes a tea during the outdoor tea ceremony at Zuihoji Temple Park on November 3, 2011 in Kobe, Japan. The tea ceremony began in 1950 to commemorate the 14th century governor Toyotomi Hideyoshi and his tea master Sen no Rikyu, who are said to visit this area and enjoyed tea ceremonies. (Photo by Buddhika Weerasinghe/Getty Images)

The pit lane is reflected in the visor of a Mercedes Formula One pit crew member during the second practice session of the Australian F1 Grand Prix at the Albert Park circuit in Melbourne March 13, 2015. REUTERS/Brandon Malone