So we were given this question in my evolutionary bio class and i completely forgot all about stats (slope regression etc). Its due tomorrow night so I would really appreciate if someone could help me out here and explain thanks!
3. Pigs are fat. Very fat. They got that way due to many years of selective breeding because fat content essentially
determines the profit of a pig. One of the classic examples of artificial selection has been these long term
programs to raise the "back fat" content of pigs.
Say we have a population of pigs and we measure the "back fat" content of each pig (with a device available at:
http://www.secrepro.com/web-eng/ultrasound/lean-meater.html). Back fat depth data for a 24 pig starting
population is given in the table below (12 males, 12 females). A breeding program to select pigs with highest fat
content is started by selecting the 6 males and 6 females with the highest amount of back fat and breeding them.
A previous study determined that the slope of the regression of mean offspring back fat depth versus parental
mean back fat depth was 0.6.
Starting pigs:
females 4.0 3.0 3.3 2.5 3.3 2.2
3.9 2.7 3.3 2.5 3.2 2.1
males 4.1 2.9 3.5 2.7 3.3 2.2
3.8 2.9 3.3 2.3 3.0 2.0
(a) What is the expected heritability of back fat depth?
(b) What mean fat content do you expect in the generation after selection? (show your work)
3. Pigs are fat. Very fat. They got that way due to many years of selective breeding because fat content essentially
determines the profit of a pig. One of the classic examples of artificial selection has been these long term
programs to raise the "back fat" content of pigs.
Say we have a population of pigs and we measure the "back fat" content of each pig (with a device available at:
http://www.secrepro.com/web-eng/ultrasound/lean-meater.html). Back fat depth data for a 24 pig starting
population is given in the table below (12 males, 12 females). A breeding program to select pigs with highest fat
content is started by selecting the 6 males and 6 females with the highest amount of back fat and breeding them.
A previous study determined that the slope of the regression of mean offspring back fat depth versus parental
mean back fat depth was 0.6.
Starting pigs:
females 4.0 3.0 3.3 2.5 3.3 2.2
3.9 2.7 3.3 2.5 3.2 2.1
males 4.1 2.9 3.5 2.7 3.3 2.2
3.8 2.9 3.3 2.3 3.0 2.0
(a) What is the expected heritability of back fat depth?
(b) What mean fat content do you expect in the generation after selection? (show your work)