You wish to understand the heritability of seed size prefere

You wish to understand the heritability of seed size preference in inbred lines of parakeets. Your assistant graphs the seed size preference of parent and offspring parakeets from line A and finds a slope of 0, and does the same for line B and finds a slope of 0.01. What do you make of these results?

Solution

When offspring values are plotted (\"regressed\") against average parent values, as in the question above, the slope of the curve gives the heritability (narrow sense heritability, i.e. h²).

Therefore, the heritability of seed size preference of inbred parakeet lines A and B is 0 and 0.01, respectively. The low values of heritability indicate that parakeets do not inherit their seed size preference from their parents, or in other words, the seed size preference in parakeets is not genetically determined by the seed size preference in their parents.