Question

at one time, giraffes had short necks, but mutations in a small number of genes over time made their necks longer. scientists claim that this was a beneficial mutation. which evidence supports the claim? giraffes with long necks ran slower than giraffes with short necks. giraffes with long necks needed more food than giraffes with short necks. giraffes with long necks ate as many leaves as giraffes with short necks. giraffes with long necks reproduced more than giraffes with short necks.

Explanation:

To determine beneficial mutation, we analyze fitness (reproductive success). A beneficial mutation increases survival/reproduction.

• Option 1: Slower speed is a disadvantage, not support.
• Option 2: Needing more food is a disadvantage, not support.
• Option 3: Eating same amount doesn’t show benefit.
• Option 4: More reproduction means the long - neck trait (from mutation) was beneficial as it increased genetic contribution to next generation.

Answer:

D. Giraffes with long necks reproduced more than giraffes with short necks.