Chapter 16, Problem 6STP

Summary Introduction

Introduction:

Hominins are a subgroup of the hominoids and has evolved in response to climate changes of the Miocene. The oldest known hominoid fossil is from the genus Proconsul . It is considered to be the human ancestor. The hominins include humans and all their extinct relatives. Homo sapiens have evolved from hominoids.

Answer to Problem 6STP

Correct answer :

The correct answer is option D. Proconsul->Australopithecus afarensis->Australopithecus africanus->Homo

Explanation of Solution

Explanation/justification for the correct answer:

Option D. Proconsul->Australopithecus afarensis->Australopithecus africanus->Homo − The first hominins that were truly bipedal were the australopithecines. Lucy is one of the complete australopithecine fossils ever found. She was a member of species A.afarensis which lived between 4 and 2.9 mya. The first australopithecine fossils found was the “Taung baby” in Africa. It was a member of species A.africanus and lived between 3.3 and 2.3 mya. So the correct sequence of hominin evolution is Proconsul->Australopithecus afarensis->Australopithecus africanus->Homo.

Hence this is the correct option.

Explanation for incorrect answer:

Option A. Australopithecus afarensis->Australopithecus africanus->Proconsul->Homo -The oldest known hominoid fossil is from the genus Proconsul . It is considered to be the human ancestor. The australopithecines came after the Proconsul . Hence this is not the correct option.

Option B. Australopithecus africanus->Australopithecus afarensis->Proconsul->Homo - The australopithecines came much later than the Proconsul . Hence this is not the correct option.

Option C. Homo->Australopithecus africanus ->Australopithecus afarensis ->Proconsul − The Homo sapiens have evolved from the australopithecines. The oldest known hominoid fossil is from the genus Proconsul . Hence this is not the correct option.