A new paper is published today on PLoS One:
Low-Temperature Stress during Capped Brood Stage Increases Pupal Mortality, Misorientation and Adult Mortality in Honey Bees
We treated honey bee brood at various ages for cold stress (20C) and then determined their mortality during both brood and adult stages and also their “mis-orientation”. The misorientation is perhaps most interesting — nearly all larvae will make the right decision in orientating their head toward the cell capping, because if they make a mistake, they will die. There is no way for a bee to make a turn inside a cell (not enough room!), so her head is toward the cell bottom and of course she will die of starvation. I estimate that a newly emerged bee will die within 6 hrs if she has no access to food. However, when brood was cooled at 20 degrees C, which is not that cold for most other insects (e.g. solitary bee pupae), as many as 40% of bees will misorient inside cells!