You are studying selection on a trait in a wild population a

You are studying selection on a trait in a wild population and you do not know the heritability of the trait, but are able to measure it in a large sample of the population. You then make careful observations about which individuals reproduced. After some time, you come back and measure the trait in the offspring of those individuals (without knowing which individuals were their parents), could you compute the heritability of this trait? How would you do it? Write down both the equation and an explanation in words. Write down the quantity you are looking for. H^2 Write down any means you know of for quantifying it. Slope of plot of midparent vs. midoffspring trait values X h^2 = R/S Write down given information. P_pop P_Pon P_off Do you have the information you need to compute? Do you have the information you need to compute missing factors? R = P_pop -P_off S = P_pop -P_set h^2 = P_pop -P_off/P_pop -P_set

Solution

1).

Heritability is a parameter that determines the relation between the genetic and environment (i.e. nurture and nature) in the inheritance of a trait. If the trait is only influenced by the genetics, the heritability is considered as 100%, if the trait is only influenced by the environment, the heritability is, 0%.

The heritability is in between 1 and zero means, it is influenced by both the genetic and environment and it changes with the change in the environment.

Broad sense heritability is the ratio of genotypic variance to the total phenotypic variance (includes the additive, dominant and epistatic variances).

H2 = Var (G)/ Var (P).

Narrow sense heritability is the phenotypic variation explained by the additive genetic variance (excludes the dominant and epistatic variances).

H2 = Var (A)/ Var (P)

To test the effect of artificial selection on live stock, we should choose narrow sense heritability because it only expresses the genetic variance due to selection.