Ingo Arndt / Christmas Island Red Crabs (Gecarcoidea natalis) crossing closed road, during annual migration, Christmas Island, Indian Ocean, Australian Territory, November 2009.

Mark Taylor / Car park flooded by River Wey, with cars almost completely submerged during Christmas 2013 flooding, Guildford. Surrey, England, UK. 25th December 2013.

Konstantin Mikhailov / Map showing Grossglockner High Alpine Road with the Hohe Tauer Ridge, Hohe Tauern National Park, Austria, Europe, May 2009

Ross Hoddinott / Tree and road sign in the snow, icy, wintry roads, early morning light, nr Bradworthy, Devon, UK. December 2010

Ross Hoddinott / Road and road sign in snow, early morning light, nr Bradworthy, Devon, Uk. December 2010

Ross Hoddinott / Tree and road sign in the snow on icy, wintry roads in early morning light, nr Bradworthy, Devon, UK. December 2010

Staffan Widstrand / Moose warning sign on roadside, Sweden.

Franco Banfi / Black bear crossing warning sign, Juneau, Alaska, United States.

Juan Carlos Munoz / Road warning sign in Portmagee Harbour, County Kerry, Republic of Ireland. September 2015.

Kerstin Hinze / European souslik / Ziesel (Spermophilus citellus) road traffic warning sign, Gerasdorf near Vienna, Austria.

Martin Gabriel / Caution sign 'Sousliks crossing the road', European souslik (Spermophilus citellus), Lake Neusiedl, Austria, April.

Cyril Ruoso / Giant panda road side sign at Chengdu Panda Breeding Center, Sichuan. China, January 2012.