Bees of foraging age learn quickly if rewarded, but don't retain a memory long without a reward. what is the adaptive benefit of this trait?

Allow them to switch from unprofitable resources

Explanation:

A trait is an phenomenon  of the whole or some portion of the development pattern of the organism. An adaptive trait is then an aspect of the development pattern that facilitates the survival and reproduction of its carrier in a certain succession of the environments. It is tempting to look for the evolutionary advantage of any traits of any organism. Everywhere is an adaptation. Of course, new adaption is there in the environment and that is full of adaptation traits and recognizing this is important. However, before the examination of the traits that are not adaptations. It will be useful to specifically define what an adaptation is and how we can determine whether or not a trait qualifies as an adaptation.

to plan an idea out before