Final answer:
The mechanism of change described in this scenario is artificial selection. Humans selectively breed cows that produce over 10 gallons of milk per day to enhance milk production in future generations.
Step-by-step explanation:
The mechanism of change described in this scenario is artificial selection. Artificial selection is a process whereby humans selectively breed organisms with desirable traits to enhance those traits in future generations. In this case, the humans are selecting cows that produce over 10 gallons of milk per day to breed, which will likely result in an increase in milk production for future generations of dairy cows.
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