lec_6_cond_13

How much change next generation average of population

Info iconThis preview shows pages 3–5. Sign up to view the full content.

View Full Document Right Arrow Icon
(How much change next generation) average of population 0 0 average of selected G=0 G=1 900 692 0 0 900 seed size (mg) average of population 404 average = 404 average = 692 average of selected G=0 G=1 Parents average of population Observed Results 0 0 900 average = 404 692 0 0 900 seed size (mg) Offspring average is in between 404 & 692 average = 609 So response to selection depends on how much phenotypic variation is due to genetic variation among individuals, i.e. heritability average seed size increased by 51% To predict future change in response to selection we need to estimate heritability. Note: The symbol for heritability is h 2 not h, so h 2 is not heritability squared 27
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
R S 692 - 404 = 288 R=609-404=205 S=692-404=288 609 - 404 = 205 relative number 0 G=0 G=1 0 0 900 seed size (mg) average = 609 To estimate heritability, we need to defne 2 parameters Selection DiFFerential = strength oF polygenic selection = AVE(selected) - AVE(whole pop) = S average oF selected Parents OFFspring 900 average = 404 692 S = To estimate heritability, we need to defne 2 parameters Response DiFFerential change in population due to polygenic selection = R AVE (whole pop.in G=1) AVE (whole pop.in G=0) = = = - 0 900 average oF selected G=0 G=1 Parents 0 0 900 seed size (mg) OFFspring 692 R average = 404 average = 609 0 900 average = 404 692 G=0 G=1 Parents 0 0 900 seed size (mg) average = 609 OFFspring Realized heritability = proportion oF polygenic selection that is maniFest in oFFspring = R / S = estimate oF heritability (h 2 ) 205 288 = 205 / 288 = 0.71 Realized heritability can be expressed as a slope with Family data slope = 1 is PER±ECT heritability slope = 0 is NO heritability Intermediate heritability Average phenotype oF oFFspring Average phenotype oF parents 28 The slope oF the average phenotype oF parents vs. the average phenotype oF their Family (oFFspring) is another way to estimate h 2 Selection Response to selection Selection & Response Average
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page3 / 5

How much change next generation average of population...

This preview shows document pages 3 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online