Chapter 15, Problem 5A

Summary Introduction

Introduction:

Charles Darwin gave a theory of natural selection. He argued that if enough time is given, natural selection could modify a population to produce new species. On the Galapagos Islands, Darwin studied many species of animals and plants that were unique to the islands but similar to species elsewhere. He studied the adaptations in giant tortoises found in Galapagos Islands which contributed to the theory of evolution.

Answer to Problem 5A

Correct answer :

The correct answer is option B. Tortoises with domed shells are younger than the tortoises with flat shells.

Explanation of Solution

Explanation/justification for the correct answer:

Option B. Tortoises with domed shells have more young than tortoises with flat shells−According to the illustration given below, the tortoise has dome shaped shell. It was found that tortoises with dome shaped shells survived better than those with flat shells. One of the principles of natural selection is that populations produce more offspring than can survive. So, tortoises with dome shaped shells produced more young ones than those with flat shells. Hence, tortoises with dome shaped shells survived.

Hence, this is the correct option.

Explanation for incorrect answer:

Option A. All tortoises look like the above tortoise. One of the principles of natural selection is that populations produce more offspring than that can survive. So, the tortoises with dome shaped shells produced more young ones than those with flat shells. Hence, tortoises with dome shaped shells survived. All tortoises do not look like the above tortoise.

Hence, this is not the correct option.

Option C. All the tortoises born on the island survive- One of the principles of natural selection is that populations produce more offspring than can survive. So, tortoises with dome shaped shells produced more young ones than those with flat shells. Hence, tortoises with dome shaped shells survived. Hence, this is not the correct option.

Option D. The tortoise shell looks nothing like the shell of either parent− One of the principles of natural selection is that populations produce more offspring than can survive. So, tortoises with dome shaped shells produced more young ones than those with flat shells. Hence, tortoises with dome shaped shells survived. Hence, this is not the correct option.