How did the Earth come to be occupied by humans? Dr. Afxendiou Global History and Geography - 9 Sachem North High School

Human Origins Most societies have origin myths There are still origin myths today but historians and other social scientists have EVOLUTIONARY EXPLANATIONS for our origins Charles Darwin – suggested in the 1800s that humans and apes had a common ancestor millions of years ago natural selection: ability to survive and reproduce otherwise extinction

How do we learn about very early history? Look for fossils and artifacts in order to reconstruct the story of our origins – ‘Where did we come from?’ ‘Who were our ancestors?’ Fossils are the physical remains of plants and animals Artifacts are the material remains of humans-objects left behind Prehistory – the period of time before written records.

HUMAN EVOLUTION First species of humans are called “australopithecines” (“southern ape-like creatures”) Then comes the genus “homo” which means human. Homo erectus (“standing upright”) – came about 1.5 million years ago. Homo neanderthalensis – about 300,000 to 30,000 years ago. About the same size as modern humans and had some of the same social practices (burial of the dead, making of similar tools)

Why are there differences in modern human populations? Paleoanthropologists agree that racial differences in human populations are simply adaptations to climate and are superficial For example: Lighter skin an adaptation to allow more exposure to sunlight in order to increase vitamin D production

Global Migration Modern humans spread out from Africa to Europe and Asia between 90,000 and 120,000 years ago Migrations were stimulated by climate change Ice ages lowered water levels and made migration easier

Early Human Migration 150,000—40,000 years ago