Question

Which of the following is the first known hominin?
• Australopithecus afarensis
• Homo habilis
• Ramapithecus sivalensis
• Ardipithecus ramidus

• A. \(1\)
• B. \(2\)
• C. \(3\)
• D. \(4\)

Hint:

Remember the basic evolutionary order: \[ \textit{Ardipithecus} \rightarrow \textit{Australopithecus} \rightarrow \textit{Homo} \] The earliest hominin among these is generally Ardipithecus ramidus.

Answer 1

The Correct Option is D

Concept:
The term hominin refers to members of the human evolutionary lineage after the split from the common ancestor shared with chimpanzees. The study of human evolution involves tracing fossil evidence to identify the earliest ancestors of modern humans. Different species evolved gradually over millions of years, showing changes in posture, brain size, dentition, locomotion, and social behavior. The evolutionary sequence of early humans includes several important genera such as: \[ \textit{Ardipithecus} \rightarrow \textit{Australopithecus} \rightarrow \textit{Homo} \] Among these, the earliest scientifically accepted hominin is generally considered to be Ardipithecus ramidus.

Step 1: Understanding Ardipithecus ramidus.
Ardipithecus ramidus lived approximately: \[ 4.4 \text{ million years ago} \] It was discovered in Ethiopia and is considered one of the earliest known hominins because it shows both ape-like and human-like characteristics. Important features include:
• Ability to walk partially upright (bipedalism)
• Reduced canine teeth compared to apes
• Transitional evolutionary characteristics
• Evidence of adaptation toward human evolution Thus, it is regarded as one of the earliest ancestors in the human lineage.

Step 2: Analyzing the remaining options carefully.
Option (1): Australopithecus afarensis
This species includes the famous fossil “Lucy.” It existed around: \[ 3.2 \text{ million years ago} \] Although very important in human evolution, it appeared later than Ardipithecus ramidus. Hence, this option is incorrect. Option (2): Homo habilis
Homo habilis belongs to the genus Homo and appeared approximately: \[ 2.4 \text{ million years ago} \] It is much later in the evolutionary timeline and therefore cannot be the first known hominin. Hence, this option is incorrect. Option (3): Ramapithecus sivalensis
Earlier, some anthropologists considered Ramapithecus to be an early human ancestor. However, modern scientific evidence classifies it closer to orangutans and not as the earliest true hominin. Therefore, this option is also incorrect.

Step 3: Final conclusion.
Among all the given options, the earliest scientifically recognized hominin is: \[ \boxed{\textit{Ardipithecus ramidus}} \] Hence, the correct answer is: \[ \boxed{(4)} \]