4.2. Dissection of the brain from the head capsule
While it is sometimes possible to take measurements from a single individual, the most robust and reliable results come from pooling multiple individuals. Depending on the size of the brain sections being used, tissue from up to 20 individuals may be needed per sample. Because the stress of being handled can affect neurotransmitter expression, collect the bees as quickly as possible. Frozen bees can be dissected immediately (preferable) or temporarily stored in liquid nitrogen. See the section on dissection of the brain from the head capsule in the BEEBOOK paper on anatomy and dissection (Carreck et al., 2013) for the method to extract the brain out of the head capsule. Place the desired brains or brain sections into a labelled 0.5 ml microcentrifuge tube. Cover and store at -80°C for up to several weeks if the samples are not to be analysed immediately.