Chapter 16, Problem 27A

Summary Introduction

Introduction : The remains or traces of ancient life which have been preserved over time by natural processes are known as fossils.

Evolution is the change in traits of a species over generations, which is mainly dependent on the natural selection.

Answer to Problem 27A

Correct answer :

The correct answer is option (a), A. africanus

Explanation of Solution

Explanation/justification for the correct answer :

Option (a) A. africanus is a genus that had lived between 3.3 and 2.3 mya. It is the first undisputed member of the hominin group.

Explanation for incorrect answer :

Option (b) H. antecessor : It is a genus that had lived 1.2 million and 0.8 million years ago.

Option (c) H. ergaster : It is a genus that had lived 1.8 to 1.2 million years ago. It is the third member of the homo group.

Option (d) H. habilis : It is a genus that had lived 2.4 to 1.4 million years ago. It is the first member of the genus homo.

Conclusion

The first undisputed member of the hominin group is A. africanus .