Learn on PengiIMPACT California Social Studies, Grade 6Chapter 1: Early Humans and the Agricultural Revolution

Lesson 1: The First Humans

Grade 6 students explore the origins of modern humans in this lesson from IMPACT California Social Studies, examining the evolutionary relationship between primates, apes, and hominins, including key species within the genus Homo. Students analyze fossil evidence, such as the Australopithecus afarensis skeleton known as Lucy, to understand how bipedalism and other physical characteristics developed over millions of years. The lesson builds foundational knowledge of early human ancestry and how scientists use fossils and skeletal remains to reconstruct prehistoric life.

Section 1

Early Ancestors Walk Upright

Key Idea

Humans belong to a group of mammals called primates, which also includes monkeys and apes. Primates share special traits like large brains and forward-facing eyes that help them understand their environment.

Millions of years ago, a new branch of the primate family tree appeared in Africa. These were the first hominins, the group that includes modern humans. The most important change for these early ancestors was the ability to walk upright on two legs, a skill known as bipedalism.

Section 2

Scientists Uncover Human Origins

Key Idea

The story of the earliest humans is a puzzle with many missing pieces. Since there were no written records, scientists must find other clues to understand the distant past.

Paleoanthropologists are like history detectives. They carefully dig for and study ancient, fossilized bones and artifacts. Each fragment provides a small piece of information about how early hominins looked and lived.

Section 3

Hominins Evolve Greater Abilities

Key Idea

Early hominins slowly developed more complex skills over millions of years. This process of hominin evolution began with groups like Homo habilis, who were the first to make simple stone tools for survival.

Later hominins built on these early skills. Homo erectus learned to control fire, and Homo neanderthalensis created better tools and formed social communities that buried their dead.

Section 4

Humans Migrate Across the Globe

Key Idea

Scientific evidence shows that modern humans first lived in Africa. Following resources and adapting to new climates, groups of these early people began a long journey. They slowly spread from Africa into Asia and Europe over thousands of years.

During the last Ice Age, lower sea levels revealed a land bridge that connected Asia and North America. Hunter-gatherer groups followed herds of large animals across this bridge. This final step brought humans into the Americas, completing their migration across the world.

Lesson overview

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Section 1

Early Ancestors Walk Upright

Key Idea

Humans belong to a group of mammals called primates, which also includes monkeys and apes. Primates share special traits like large brains and forward-facing eyes that help them understand their environment.

Millions of years ago, a new branch of the primate family tree appeared in Africa. These were the first hominins, the group that includes modern humans. The most important change for these early ancestors was the ability to walk upright on two legs, a skill known as bipedalism.

Section 2

Scientists Uncover Human Origins

Key Idea

The story of the earliest humans is a puzzle with many missing pieces. Since there were no written records, scientists must find other clues to understand the distant past.

Paleoanthropologists are like history detectives. They carefully dig for and study ancient, fossilized bones and artifacts. Each fragment provides a small piece of information about how early hominins looked and lived.

Section 3

Hominins Evolve Greater Abilities

Key Idea

Early hominins slowly developed more complex skills over millions of years. This process of hominin evolution began with groups like Homo habilis, who were the first to make simple stone tools for survival.

Later hominins built on these early skills. Homo erectus learned to control fire, and Homo neanderthalensis created better tools and formed social communities that buried their dead.

Section 4

Humans Migrate Across the Globe

Key Idea

Scientific evidence shows that modern humans first lived in Africa. Following resources and adapting to new climates, groups of these early people began a long journey. They slowly spread from Africa into Asia and Europe over thousands of years.

During the last Ice Age, lower sea levels revealed a land bridge that connected Asia and North America. Hunter-gatherer groups followed herds of large animals across this bridge. This final step brought humans into the Americas, completing their migration across the world.