Magpie Funeral

Some time Saturday evening or Sunday morning, a magpie died in the parking lot behind my appartment. I first found out when I heard the distinctive call of a magpie funeral. The first magpie on the scene seems to act as a coroner, making sure the one on the ground really is dead. This is done with sharp and forceful strikes to the head and neck. It's not easy to take a pulse through feathers. Within fifteen minutes, six other magpies arrived on the scene. They all circled in close and took turns swooping past the corpse. Then, one by one, they flew off again. They gathered again a few hours later, swooped in close, but didn't bother confirming that their comrad was still dead. I really wish that I knew the evolutionary reasons for a magpie funeral. Magpies have very open societies, with large groups sharing a territory, so it can't be to divide up the fallen bird's territory as is done by other types of birds. Also, it can't be an anti disease or anti-scavenger strategy, since they would all be exposed to whatever pathogen was responsible for the kill, and if I can recognize the funeral call, any scavenger can.