Question: Consider the following data on bill length in Darwin’s finches (this is a very small sample of th…
Show transcribed image text Consider the following data on bill length in Darwin's finches (this is a very small sample of the actual data from a study conducted by Peter and Rosemary Grant for 30 years in the Galapagos). These quantitative trait values (in mm) are given for both parents and one offspring for each parent pair. b) Calculate the midparent values for each parent pair. Use a midparent-offspring regression approach to calculate the horitability of this trait. There is more than one way to do this, but it will be easiest if you use Microsoft Excel. You can use the VARP function to calculate the necessary variances and the COVAR function to calculate the covariance. Remember that the slope of the regression line is the Cov(Midparent,Offspring)/Var(Midparent). You can calculate these by hand if you want, but it will be time consuming. You can also use Excel to plot offspring value as a function of midparent value, and then have Excel fit a regression line. Then, you can get ihe heritability by knowing the relationship between the slope and the heritability (from class) Report the heritability here. c) Now calculate the hentability (h^2) for the trait using a mother-offspring regression and a father-offspring regression. Are they the same? Remember to calculate the correct value for h^2 (see middle slide from pg 9 from the "Lecture_09 Phenotypic_evolution.pdf" set for details).
Consider the following data on bill length in Darwin's finches (this is a very small sample of the actual data from a study conducted by Peter and Rosemary Grant for 30 years in the Galapagos). These quantitative trait values (in mm) are given for both parents and one offspring for each parent pair. b) Calculate the midparent values for each parent pair. Use a midparent-offspring regression approach to calculate the horitability of this trait. There is more than one way to do this, but it will be easiest if you use Microsoft Excel. You can use the VARP function to calculate the necessary variances and the COVAR function to calculate the covariance. Remember that the slope of the regression line is the Cov(Midparent,Offspring)/Var(Midparent). You can calculate these by hand if you want, but it will be time consuming. You can also use Excel to plot offspring value as a function of midparent value, and then have Excel fit a regression line. Then, you can get ihe heritability by knowing the relationship between the slope and the heritability (from class) Report the heritability here. c) Now calculate the hentability (h^2) for the trait using a mother-offspring regression and a father-offspring regression. Are they the same? Remember to calculate the correct value for h^2 (see middle slide from pg 9 from the "Lecture_09 Phenotypic_evolution.pdf" set for details).
