Why is the date 1.8 million years ago (mya) considered significant in hominin evolutionary history?

• A. It is when the first evidence of controlled use of fire was found.
• B. It marks the earliest known migration of Homo erectus out of Africa.
• C. It corresponds to the extinction of Australopithecus afarensis.
• D. It is the estimated time when Homo sapiens first appeared.

Answer: (B)

Verified step by step guidance

1. Understand the context of hominin evolutionary history: Hominins are a group that includes modern humans, their ancestors, and other extinct relatives. Key events in this history are often marked by significant behavioral, anatomical, or migratory milestones.
2. Identify the significance of 1.8 million years ago (mya): This date is associated with the earliest known migration of Homo erectus out of Africa, a major event in human evolution.
3. Clarify the role of Homo erectus: Homo erectus is an extinct species of hominin that exhibited advanced traits such as larger brain size and the ability to use tools. Their migration out of Africa represents the first known instance of hominins spreading to other continents.
4. Eliminate incorrect options: The controlled use of fire occurred later in hominin history, Homo sapiens appeared much later (approximately 300,000 years ago), and Australopithecus afarensis went extinct earlier than 1.8 mya.
5. Conclude the significance: The migration of Homo erectus out of Africa at 1.8 mya marks a pivotal moment in hominin evolutionary history, showcasing adaptability and the ability to colonize new environments.