I assume that this is due to poor mixing of the sperm in the queen, and
if it happens in the way that is noticeable by colour it probably occasionally
happens as well when the differences are not obvious.

Reply:
This LIFO and FIFO has been talked about in the past much and whether queen or whether not queen can adjust/shift sperm at will, but is not something most all beekeepers look at in rearing of queens unfortunately and how it works, due to artificial insemination coming on board and the stirring of all sperm together......which to me is not natural in a way. But much research was paid for on this to few good O/S researcher(s) way back.......
 
Dee




      

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