Good guess Snap! Yup - they remove mites from the pupa. The mites ride around on the adults then jump into an open cell containing a pupa and feed away. Some bees somehow detect the mites and remove them. We have other lines that are resistant to mites for other reasons, too. I'm trying to find the genes associated with the mite removal behavior and others. Fun stuff! I just got in a new piece of equipment yesterday (I've been waiting for it for 9 months). This will make things progress much faster!

Mimi - you wouldn't believe how many definitions of "grooming" there are! It's crazy!