What happens after death?

Death is, of course, a natural part of the 'cycle' of life, so there's no getting away from it, even though it's sad when the time comes for our bees to go to the "great big hive in the sky".  

Over the last few weeks we've seen a few deaths and finally today I downloaded some of the footage from the CCTV system. This may seem unduly morbid, but it turns out we were observing some behaviour we hadn't expected. 

A few weeks ago a bee had died and we saw one of its siblings drag it up through the nest layers to a position just under the camera. In the process it seemed to be trying to revive it, even dragging it to the area where the sugar-water wick was. Here's the video:

This seemed to be quite interesting but we thought no more of it until earlier this week we noticed two more stationary bees had appeared in the same location. I went over the CCTV footage to find what had happened and when. What I discovered was that one bee had made its way (very slowly) to the leftmost position on the camera and, sadly, over the course of two hours gradually subsided into stillness.  It seemed probably just a mere coincidence to find two in the same place - especially since we can only see about a sixth of the nest and anything similar could be going on elsewhere.

However, the following dayI was amazed to see the following footage. Very similar to the first with a sibling bee dragging a dead bee to its final resting place. But the intriguing thing is that the location is the same and behaviour ever so similar. In this clip a second bee comes along 5 minutes later and re-arranges things slightly. Here it is:

The whole thing leaves me rather intrigued and wondering whether Bumblebees are known to treat their sick and dead bees in this way? Is this co-incidence or indicative of some kind of organised behaviour? I've not found any other studies yet that answer that question.