Massimo 
The bumblebee queen learns how to use the protective cap in less than 24 hours.
Daniel Beneš@Rainmaker1973 Won't that damage her eyes? Evolution hasn't equipped her for that kind of behavior.
Dirk Willrodt@howking @Rainmaker1973 in the wild they would dig holes (well some species do) or have to move debris from leaves to sticks that fell on their entrance.
Also many flowers are very tight (this helps to adhere the pollen to the bee) and they have to push their way in. I am pretty sure that compound eyes are very resilient, having no natural protective layer like eyelids.
Also many flowers are very tight (this helps to adhere the pollen to the bee) and they have to push their way in. I am pretty sure that compound eyes are very resilient, having no natural protective layer like eyelids.