A section of multi-vehicle accident on Interstate 75 is shown in Detroit, Thursday, January 31, 2013. Snow squalls and slippery roads led to a series of accidents that left at least three people dead and 20 injured on a mile-long stretch of southbound I-75. More than two dozen vehicles, including tractor-trailers, were involved in the pileups. (Photo by Paul Sancya/AP Photo)

Employee of ornithological flight support service Nika Ryzhova-Alenicheva holds her hawk, which is used to control fauna to avoid bird strikes during takeoffs and landings, at Domodedovo airport outside Moscow, Russia September 2, 2016. (Photo by Maxim Zmeyev/Reuters)

Man prepares wigs as he waits for customers in downtown Johannesburg, on August 5, 2014. Some estimates put Africa's dry hair industry at as much as $6 billion a year; Nigerian singer Muma Gee recently boasted that she spends 500,000 naira ($3,100) on a single hair piece made of 11 sets of human hair. (Photo by Siphiwe Sibeko/Reuters)

A man sleeps between tombstones in front of his single-room home on a hot night in the Cairo Necropolis, Egypt, October 13, 2015. In the sprawling Cairo Necropolis, known as the City of the Dead, life and death are side by side. Amid a housing crisis in Egypt, and with the population of greater Cairo estimated at about 20 million, people count themselves lucky to have a place to call home in the graveyards that date back hundreds of years. (Photo by Asmaa Waguih/Reuters)

Kale grows at Kajodlingen farm in Gothenburg, Sweden, September 28, 2016. They are doing it on the rooftops, on tower block balconies and even on a disused railway: Swedes have discovered a passion for urban gardening as a way of growing fresh food and getting back in touch with nature. Part of a global movement, an increasing number of Swedish city-dwellers are growing their own in window boxes and allotments or are visiting public gardens built in or on industrial or office spaces. (Photo by Maxim Shemetov/Reuters)

Space shuttle Discovery sits atop NASA's 747 Shuttle Carrier Aircraft (SCA) ready to transport it from Kennedy Space Center to the Washington D.C., on April 17, 2012 in Cape Canaveral, Florida. Following the retirement of the shuttle fleet, Discovery will fly to Washington for display at the Smithsonian's National Air and Space Museum. (Photo by Lofty Ambitions)

These are the ambitious plans which suggest skyscrapers of the future may house an entire city. The Endless City project is an award-winning proposal by sure Architecture, who propose turning skyscrapers into complete ecosystems. London is the proposed city for the mixed-use tower – which would feature huge ramps linking different sections of the structure. The company, whose design won the SkyScrapers and SuperSkyScrapers Competition, insist the structure would be a great space-saver in dense cities which have previously spread outwards rather than upwards. (Photo by Caters News)

“The RSPB’s Snettisham Nature Reserve lies on the edge of The Wash, one of the most important bird estuaries in the United Kingdom. The Wash, on England’s east coast, supports over 300,000 birds, and Snettisham sometimes holds more than a third of them”. – The Palm Beach Post. Photo: Waders flock together seeking new feeding grounds during the incoming tide. (Photo by Dan Kitwood/Getty Images via The Palm Beach Post)