Conjoined twins Angelica (C) and Angelina Sabuco (L) play with child life specialist Allison Brooks during a press conference at the Lucile Packard Children's Hospital at Stanford on October 31, 2011 in Palo Alto, California. Two year-old conjoined twins Angelica and Angelina Subaco who are connected at the chest and abdomen are preparing for separation surgery by Dr. Gary Hartman. The surgery will last between 6 and 8 hours that is followed by three hours of reconstructive surgery for each girl. (Photo by Justin Sullivan/Getty Images)

Tree trunks are seen in a forest on November 8, 2011 near Landau an der Isar, Germany. The German government is conducting a nationwide project to estimate the number, variety and geographic distribution of trees and forests in Germany, as well as their condition and health. Approximately a third of Germany is covered in woodlands, and though that territory has actually expanded since 1989, some analysts fear demand for wood will outstrip supply in coming years due to national growth in industry and bio-energy needs. (Photo by Johannes Simon/Getty Images)

Assistant Manager Jayesh Vaghela brushes a vintage silk top hat at Lock & Co. Hatters on March 22, 2011 in London, England. Founded in St. James's in 1676, when Charles II was on the throne, this family owned business has provided hats for Royalty and the gentry for over 300 years. Staff report that sales of formal hats are booming ahead of the wedding of Prince William and Kate Middleton in Westminster Abbey on April 29, 2011.

Yingluck Shinawatra speaks with members of Parliament as the Thai parliament officially elected her as the country's first female Prime Minister August 5, 2011 in Bangkok, Thailand. In the lower house, 296 of the legislature's 500 members voted for Yingluck. Three members voted against and 197 abstained.Thai's cast their ballots back on July 3, 2011. Yingluck Shinawatra, is the younger sister of fugitive former premier Thaksin Shinawatra, who was ousted in a 2006 coup. This is Thailand's 4th election on 7 years as the country continues on a bumpy road to democracy.
(Photo by Paula Bronstein /Getty Images)

A fisherman is seen standing on a cliff edge at Cape Bank in La Perouse on February 20, 2011 in Sydney, Australia. The practice of fishing from rock platforms, cliffs and rocky outcrops is notoriously dangerous with many anglers per year being washed into the ocean by dangerous surf or unexpected large waves. Angling is often reported as the sport having the highest mortality rate on average due to fishermen drowning with rocking fishing contributing to a high number of these deaths. (Photo by Mark Kolbe/Getty Images)

Pilgrims wearing traditional dresses take part during the Queen of Angeles pilgrimage in Alajar, southern Spain, September 8, 2015. Every year, devotees converge at the Arias Montano crag to pay homage to the Queen of Angeles during an annual pilgrimage which combines religious fervour and festive colour. (Photo by Marcelo del Pozo/Reuters)

Jing Li (L) and her husband Ke Xu wear Tibetan traditional costumes as they pose for their wedding photos in front of Tibetan prayer flags at the Nianqing Tanggula mountain pass in the Tibet Autonomous Region, China November 18, 2015. Jing, 22, and her husband Ke Xu, 23, both from Shiyan in northwestern Hubei province live in Tibet for three year. The couple married last month. (Photo by Damir Sagolj/Reuters)

An ice covered entrance door to the international gene bank Svalbard Global Seed Vault (SGSV) near Longyearbyen on Spitsbergen, Norway, October 20, 2015. Two consignments of crop seeds will be deposited next year in a “doomsday vault” built in an Arctic mountainside to safeguard global supplies. The vault, which opened on the Svalbard archipelago in 2008, is designed to protect crop seeds, such as beans, rice and wheat against the worst cataclysms of nuclear war or disease. (Photo by Anna Filipova/Reuters)