7.4 - Selective breeding
Selective breeding
● ***“Artificial selection”
● E.g.: improvement in crop yield
● E.g.2: tamed (被馴化) animals (often domestic) from wolves to dogs
● Allows social transition from hunting (unstable food source) to agriculture (stable ``)
● Desired characteristics from a mixed population bred together; continues over
many generations
○ ***E.g.: insect resistance in crops, higher crop yield, domestic animals with a
gentle nature (acting as agricultural helpers)
○
Advantages & disadvantages of selective breeding
● Inbreeding (近親繁殖) offspring more prone to inheriting genetic diseases
(mutations - often present in recessive alleles); narrowed-down gene pool (基因庫)
● Faster way of selective breeding - genetic engineering (directly modifying genetic
code)
1
Selective breeding
● ***“Artificial selection”
● E.g.: improvement in crop yield
● E.g.2: tamed (被馴化) animals (often domestic) from wolves to dogs
● Allows social transition from hunting (unstable food source) to agriculture (stable ``)
● Desired characteristics from a mixed population bred together; continues over
many generations
○ ***E.g.: insect resistance in crops, higher crop yield, domestic animals with a
gentle nature (acting as agricultural helpers)
○
Advantages & disadvantages of selective breeding
● Inbreeding (近親繁殖) offspring more prone to inheriting genetic diseases
(mutations - often present in recessive alleles); narrowed-down gene pool (基因庫)
● Faster way of selective breeding - genetic engineering (directly modifying genetic
code)
1
