A male and female giraffe live on a small island in the Indian Ocean. One giraffe has a long neck and one has a short neck. On the island grow many tall trees and many short trees. The trees are the giraffes' only source of food. The giraffe with the short neck, however, cannot reach the leaves of the tall trees, so its only available food source is the leaves of the short trees.  The two giraffes reproduce. Of their six offspring, three have long necks and three have short necks. A swarm of beetles lands on the island and begins to eat the leaves of the short trees. The beetles don't like the taste of the leaves of the tall trees, so they leave them alone. The beetles eat the leaves of many of the short trees. Since the giraffes with short necks cannot reach the leaves of the tall trees, some of them die. The remaining giraffes reproduce. Since fewer short-neck giraffes are alive to reproduce, more of the offspring have long necks. Finally, the beetles have eaten the leaves of the short trees. Only the tall trees have leaves. The short-neck giraffes cannot reach the leaves of the tall trees, so they die. Only the long-neck giraffes survive. Now, there are only long-neck giraffes left to reproduce. In future generations, all of the offspring on this island have long necks.

Question: Review the data that was collected concerning the distance traveled by individuals categorized by short or long legs. Which trait may have the greatest chance of being passed down to future generations of lizards-short legs or long legs?