By Caroline Wyatt
Defence correspondent, BBC News
One marine sports the Sherlock Holmes look (Pic: MoD)
The Royal Marines have found a novel way to keep a stiff upper lip while fighting the Taleban in Helmand Province this Christmas - by holding a "moustache contest".
The marines of 40 Commando are vying to see who can grow the most outrageous piece of face furniture in a competition that will be judged by a panel of their peers on Boxing Day.
The conditions the men are living in may be basic in the extreme, and the fierce battles they find themselves in often hair-raising, but judging by some of the photos sent in by Royal Marine competitors, the men themselves are hairier.
What the Duke of Wellington once said of his own troops is clearly still true today: "I don't know what they do to the enemy, but by God, they frighten me."
Second in Command of 40 Commando, Major Alex Murray, terms the competition a "morale-boosting bit of fun".
"Generations of our forefathers have been marching around these hills with the most splendid array of facial hair," he says. "We found throughout history, the upper lip has been stiffened with a good moustache.
"Some aspects of warfare are timeless, and in this case the requirement for impressive facial hair is as important today as it was for our forefathers working on the North West Frontier.
Another opts for a more Central American feel (Pic: MoD)
"Generations of British marines have operated in places like Afghanistan over the last two centuries. Often working in austere conditions, a good tash has proved essential in maintaining the stiff upper lip, and north Helmand in the current clime is no exception."
Clearly, when the terrain is harsh, and the conditions the men live and fight in are - at best - austere, there is a need for a little light Christmas distraction.
Major Murray says: "The moustache competition is really just a bit of fun and light relief in an environment that is otherwise deadly serious.
"Daily the marines and soldiers of 40 Commando are doing amazingly brave acts alongside our comrades from the Afghan National Army and police, and life can be pretty intense.
But one younger competitor cannot produce much at all (Pic: MoD)
"Morale-boosting bits of fun like this go a long way to defusing the tension and keep everyone cheerful.
"Morale in the unit is especially high at the moment, especially with the added support of family and friends and the wider public over the Christmas period. They are constantly in our thoughts and we look forward to our return in a few months time."
The marines are not the only ones working over Christmas; most of the 7,800 men and women serving in Afghanistan will be on duty on Christmas Day, working as normal, whether on the front lines or as support and logistics staff back at the main British bases.
However, few will be sporting quite the tash-tastic facial hair of 40 Commando the Royal Marines.