Expansion of Homo Sapiens
Our species evolved not much more than 150,000 years ago, making us young compared to other hominid species, some of which survived for more than a million years. Yet in the short time that we have existed, we have populated the entire globe. Many scholars think innovations like language, creative expression and sophisticated tools helped modern humans gain an advantage over other hominids and eventually drive them out of existence. Indeed, we are so successful that today Homo sapiens is the only living species of hominid around the world.
Lake Mungo, Australia
Fossil remains of Homo sapiens found at Lake Mungo, in southern Australia, are 42,000 years old, and artifacts unearthed near the site may be even older. Researchers believe that modern humans have been living in Australia for up to 60,000 years.
How Did Modern Humans Spread Around the Globe?
Most people migrated on foot, although some also navigated large stretches of open water. These migrations almost certainly took thousands of years and many generations. People probably settled in one location for a while, perhaps moving on when food or other necessities became scarce.
- The first modern humans to leave Africa probably left through what is now Egypt, but spread no farther than the Middle East (c. 100,000 years ago).
- Humans must have used boats to cross the 100 kilometers (60 miles) of water that separated Australia from Asia (up to 60,000 years ago).
- The first Americans likely arrived by walking over the Bering Land Bridge that connected Asia and North America (20,000-15,000 years ago).
- Some scholars have suggested early Americans might have used boats to move down the coast of North America, bypassing the massive ice sheets that almost completely covered what is now Canada.
Modern Humans in Asia
Once modern humans left Africa, they moved quickly into Asia. By 40,000 years ago, they had reached what is now Indonesia. This skull, from Niah Cave on the island of Borneo, may be even more than 40,000 years old.
Arrival in Australia
Modern humans seem to have reached Australia by about 60,000 years ago; a skull from Lake Mungo, for example, dates back some 42,000 years. The voyage from Asia to Australia would have required a seaworthy boat. As yet, scientists have not found remains of any such boats, but it is clear the trip would have been impossible without one.
Reaching the Americas
A skull of a female Homo sapiens from the La Brea Tar Pits in Los Angeles is 9,000 years old. Scholars are uncertain exactly when people reached the Americas. Estimates range from as far back as 30,000 to as recently as 13,000 years.
First appearing in Africa around 150,000 years ago, our species, Homo sapiens, now populates the entire world. Our closest relatives have died out, and we have survived to become the only living hominid. What makes us different physically from hominids of the past? To the unpracticed eye, the skeleton of a modern human may seem quite similar to those of our extinct hominid relatives. But a number of features set the modern skeleton apart. These traits help define a very distinctive species.
Modern humans have African roots, but around 100,000 years ago, we began spreading around the globe. This artist's reconstruction is based on fossil remains found at Cro-Magnon, a rock shelter in western France, where evidence of Homo sapiens dates back some 30,000 years.
Examine the Evidence: The modern human
What makes us modern? Scientists have identified skeletal features that all Homo sapiens share, whether they lived 100 or 100,000 years ago.
- high, vertical forehead
- small nasal aperture
- cylindrical rib cage
- narrow pelvis
A Very Modern Human
Although our lives are vastly different from the lives of our ancestors 150,000 years ago, we are physically identical.