ANSC 313 Lecture Notes - Lecture 11: Genetic Drift, Mutation Rate, Mutation
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Hardy- Weinburg Equilibrium!
2. migration!
"cattle!
"- purchase new bulls!
"- keep heifer replacements!
year 1!
buy new bull!ā¢
for ~25-30 cows!ā¢
year 2!
use last years bull on the same 25 cows and keep some heifer calves!ā¢
note all the heifers are half-sisters to each other and daughters of the cow!ā¢
year 3!
buy new bulls so he does not bred his daughters!ā¢
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HORSES!
stable may be founded on one stallion!ā¢
buy or brings in mares!ā¢
POULTRY!
total in- total out!ā¢
PIGS!
both sexes are purchased!ā¢
but not all at one time!ā¢
!
3. Mutation!
mew= mutation rate!
normally very low!ā¢
no attempt to increase this!ā¢
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4. "large" population!
if not - genetic drift occurs!ā¢
small subpopulations become increasingly diļ¬erent over generations!ā¢
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5. Selection!
natural selection " survival of the ļ¬ttest"!ā¢
ability of certain individuals, with certain traits to survive and reproduce!ā¢
hard to have this because of natural selection!ā¢
no artiļ¬cial selection!
choice of certain animals as breeding stock, based on certain traits!ā¦
note: occasionally this operates counter to natural selection!ā¦
i.e. domestic turkeys that can't copulate!ā¦
!ā¦
!ā¦
ļ¬tness(w)!ā¢
ability to contribute to the gene pool of the next generation!ā¦
"0-1!
Coeļ¬cients of selection (s)!
measures of loss of ļ¬tness!ā¢
"0-1!
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