Question

Giraffes use their extremely long necks to reach the leaves high up on acacia trees, which other animals cannot reach, giving them a food source for which they have few competitors. What can you conclude about natural selection from this observation?
a. Giraffe necks get longer over a lifetime of stretching, and their offspring inherit the longer necks of their parents.
b. All giraffes are born with short necks and, eating acacia leaves causes them to stretch over a lifetime.
c. Other animals will mimic the giraffe and grow longer necks.
d. The giraffes with the longest necks survive and produce offspring.

Answer 1

Answer: d. The giraffes with the longest necks survive and produce offspring.

Natural selection can be defined as a differential survival and reproduction. In this the organism having a favorable phenotypic advantage has better chances of survival and reproduction as compared to the other. The given situation is an example of natural selection. The long neck of giraffes is a phenotypic advantage that helps in deriving food as compared to it's competing herbivorous species. Thus, giving them a chance to survive and produce offsprings.  

Answer 2

I believe it would be D, since the animals that had more food, and a advantage, would produce and so on.