50,000 Descend Upon Rio De Janeiro For Rio+20 Earth Summit

RIO DE JANEIRO, BRAZIL - JUNE 20: Indigenous protesters gather during a march through the decades-old Vila Autodromo squatter settlement before demonstrating outside an entrance to the Rio + 20 conference on June 20, 2012 in Rio de Janeiro, Brazil. Residents of the favela are facing possible eviction for construction of an “Olympic Park” in the area. Evictions are occurring in slums throughout the city amid preparations for the 2014 World Cup and 2016 Summer Olympics. The protesters oppose Brazil’s Amazon forest policies including the controversial Belo Monte dam project. Over 100 heads of state and tens of thousands of participants and protesters have descended on Rio de Janeiro, Brazil, for the June 20-22 high-level portion of the Rio+20 United Nations Conference on Sustainable Development or 'Earth Summit.'Host Brazil is caught up in its own dilemma between accelerated growth and environmental preservation. The Brazilian Amazon, home to 60 percent of the world’s largest forest and 20 percent of the Earth’s oxygen, remains threatened by the rapid development of the country. The summit aims to overcome years of deadlock over environmental concerns and marks the 20th anniversary of the landmark Earth Summit in Rio in 1992, which delivered the Climate Convention and a host of other promises. Brazil is now the world’s sixth largest economy and is set to host the 2014 World Cup and 2016 Summer Olympics. (Photo by Mario Tama/Getty Images)