Yangman is an alien from Sisophinis Beta, masquerading as a Canadian. Despite going on many expeditions, none of his fellow geohashers have figured this out. Either he is a good actor or the Vancouverites are crazy.
It is well known that these aliens must not have their arms covered. The consequences of such an action are too terrible to be committed to paper (or monitors). This explains the multitude of short sleeved shirts he is seen in.