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!•
for ~25-30 cows!•
year 2!
use last years bull on the same 25 cows and keep some heifer calves!•
note all the heifers are half-sisters to each other and daughters of the cow!•
year 3!
buy new bulls so he does not bred his daughters!•
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HORSES!
stable may be founded on one stallion!•
buy or brings in mares!•
POULTRY!
total in- total out!•
PIGS!
both sexes are purchased!•
but not all at one time!•
!
3. Mutation!
mew= mutation rate!
normally very low!•
no attempt to increase this!•
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4. "large" population!
if not - genetic drift occurs!•
small subpopulations become increasingly different over generations!•
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5. Selection!
natural selection " survival of the fittest"!•
ability of certain individuals, with certain traits to survive and reproduce!•
hard to have this because of natural selection!•
no artificial selection!
choice of certain animals as breeding stock, based on certain traits!◦
note: occasionally this operates counter to natural selection!◦
i.e. domestic turkeys that can't copulate!◦
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fitness(w)!•
ability to contribute to the gene pool of the next generation!◦
"0-1!
Coefficients of selection (s)!
measures of loss of fitness!•
"0-1!
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