6 Predicting the Response to Selection
You are now in a position to use the three numbers you have recorded on the Bugsville worksheet to predict the average spot count among the descendants of the parents you have moved to Right Field.
The selection differential is the difference between mean of your Right Field population—that is, your selected population—versus the mean of the Left Field population before you moved any bugs to Right Field.
The selection differential is a measure of how stringently you have filtered the Left Field population in choosing the founders of your Right Field population.
You can predict the response to selection by multiplying your selection differential by your estimate of the heritability.
The response to selection is the difference between the mean of the offspring of the selection parents versus what the mean would have been if you had used all of the bugs in Left Field as founders of the right field population.