Leg-gun: the new selfie trend started by Ai Weiwei

Selfie trends come and selfie trends go, but very few carry the pedigree of the leg-gun. It was started by Chinese artist Ai Weiwei on Instagram four days ago, clad only in shorts, socks and a straw hat, pointing his own leg in the manner of a rifle.

Since then, his Instagram account has been filled with images of people from around the world holding the pose, some tagged #endgunviolence -- although this seems to have been added later by others, not Ai Weiwei himself.

Just what Ai Weiwei meant is unknown. Around the same time as the selfie, the artist also posted an image from Chinese ballet Red Detachment of Women, one of the eight model operas designed to reform the Chinese cultural stage from themes of kings and emperors to workers and soldiers during the Cultural Revolution in the 1960s and 70s.

This would fit with Ai Weiwei's activism, which often involves using social media to call out the Chinese government. The Guardian also points out that the caption on the first images translates as "Beijing anti-terrorism series", which could be a reference to the recent 25th anniversary of the student protests in Tiananmen Square, Beijing.

However, Ai Weiwei isn't stating one way or another what it's about, letting people come up with their own interpretations (as the #endgunviolence hashtag indicates). For whatever reason, though, the image has been resonating around the globe, sparking an international conversation about oppression, violence, art, freedom and fun.

Even when making a meme, Ai Weiwei doesn't do anything by halves.