A couple hugs while standing near a Christmas tree made out of plastic bins and plastic hampers outside the Museum of History in Monterrey, Mexico, December 4, 2015. The humble Christmas tree has a rich history, from evergreen trees used to symbolise eternal life in Ancient Egypt to tree worship among pagan Europeans. The modern version has its origins in Germany, where the song “O Tannenbaum” is still a festive favourite. Today the traditional tree with lights and decorations appears in cities including Washington, Moscow and Beirut. Alternative constructions range from recycled rubbish in Mexico City to old window frames in Rakvere, Estonia. Whatever the shape or size, the message is the same: Merry Christmas. (Photo by Neil Hall/Reuters)

The Tree Projects team spent 67 days documenting one eucalyptus regnans in the Styx valley of Tasmania. Using a combination of tree-climbing and elaborate arboreal rigging techniques, they produced an intimate portrait from an impossible perspective of one of the world’s largest individual flowering trees, which goes by several common names. These photos document the process that resulted in an extraordinary ultra high-definition photograph. Here: Haley nears the top of the tree. (Photo by Steven Pearce/The Tree Projects/The Guardian)

A Palestinian woman sorts freshly picked dates during harvest season in Khan Younis in the southern Gaza Strip October 4, 2015. (Photo by Ibraheem Abu Mustafa/Reuters)

A tourist stands on the shore of a private beach in Naama Bay, Sharm el-Sheikh, south Sinai, Egypt, Sunday, November 8, 2015. Britain's foreign secretary says airport security in many cities will need to be overhauled if it is confirmed the Russian plane crash in the Sinai was caused by a bomb planted by the Islamic State group or someone inspired by the militants. (Photo by Vinciane Jacquet/AP Photo)

A dressed reveler looks up to the famous cathedral in Cologne, Germany, Wednesday, November 11, 2015. Thousands of carnival supporters celebrate the traditional beginning of the carnival season in Germany. (Photo by Martin Meissner/AP Photo)

A Grey Seal pup and it's mother lay in the mud at the Lincolnshire Wildlife Trust's Donna Nook nature reserve on November 24, 2014 in Grimsby, England. Seal pup numbers have increased on last year with over 800 pups born at the reserve so far. Large bull seals are the first to arrive at the reserve in late October or early November where they will wait for females. (Photo by Dan Kitwood/Getty Images)

A merino lamb attempts to jump out of its enclosure to find its mother shortly before feeding time at the Educational and Reserach Station for Animal Breeding (Lehr- und Versuchsanstalt fuer Tierzucht und Tierhaltung, or LVAT) in Brandenburg state on January 27, 2012 in Gross Kreutz, Germany. Hundreds of lambs have been born at the LVAT in recent weeks in the midst of the station's lambing season. Many of the lambs will be sold just before Easter, when they will have grown to a weight of over 40kg, as lamb is the traditional German Easter meal. (Photo by Sean Gallup/Getty Images)

Fishermen prepare fish from their vessels on the shores of the Gulf of Aden in the city of Bosasso, northern Somalia's breakaway Puntland region December 17, 2016. (Photo by Feisal Omar/Reuters)