Show Menu

Selection Cheat Sheet (DRAFT) by

reviewer for Animal Breeding

This is a draft cheat sheet. It is a work in progress and is not finished yet.

ΔG or R is due to:

1. artificial selection among ADULTS of parent generation
2. natural differ­ences in FERTILITY among indivi­duals of PARENT generation
3. natural differ­ences in VIABILITY among indivi­duals of OFFSPRING generation
response to selection (R)
= change in population mean due to selection
= mean phenotypic value of offspring generation — mean of whole parental generation before selection
measure of selection applied = selection differ­ential = S
= mean phenotypic value of indivi­duals selected as parents
= expressed as a deviation from the population mean


process in which certain indivi­duals in a population are preferred to others for the production of the next generation
does not create new genes
to increase f (desirable genes)
to decrease f (undes­irable genes)
on the basis of phenotype
on the basis of breeding value
Basic Effect:
on the basis of breeding value
changes the array of gene freque­ncies (although almost completely hidden)
→ can be observed through changes in the MEAN
How to Describe Change:
compare successive genera­tions at the same point in the life cycle of the indivi­duals

How to Describe Change: