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Homo sapiens and early human migration

Homo sapiens evolved from their early hominid predecessors between 200,000 and 300,000 years ago and developed a capacity for language about 50,000 years ago.

Overview

  • Homo sapiens, the first modern humans, evolved from their early hominid predecessors between 200,000 and 300,000 years ago. They developed a capacity for language about 50,000 years ago.
  • The first modern humans began moving outside of Africa starting about 70,000-100,000 years ago.
  • Humans are the only known species to have successfully populated, adapted to, and significantly altered a wide variety of land regions across the world, resulting in profound historical and environmental impacts.

Where do we begin?

Before we tell the stories that make up world history, it is useful to ask: where do we begin? Where did our human stories start?
Homo sapiens is part of a group called hominids, which were the earliest humanlike creatures. Based on archaeological and anthropological evidence, we think that hominids diverged from other primates somewhere between 2.5 and 4 million years ago in eastern and southern Africa. Though there was a degree of diversity among the hominid family, they all shared the trait of bipedalism, or the ability to walk upright on two legs. start superscript, 1, end superscript

Evolution

Scientists have several theories about why early hominids evolved. One, the aridity hypothesis, suggests that early hominids were more suited to dry climates and evolved as the Africa’s dry savannah regions expanded.
According to the savannah hypothesis, early tree-dwelling hominids may have been pushed out of their homes as environmental changes caused the forest regions to shrink and the size of the savannah expand. These changes, according to the savannah hypothesis, may have caused them to adapt to living on the ground and walking upright instead of climbing. squared
Hominids continued to evolve and develop unique characteristics. Their brain capacities increased, and approximately 2.3 million years ago, a hominid known as Homo habilis began to make and use simple tools. By a million years ago, some hominid species, particularly Homo erectus, began to migrate out of Africa and into Eurasia, where they began to make other advances like controlling fire. cubed
Picture of a Homo habilis skull on a blue background. Skull is missing two of its front teeth.
Homo habilis skull. Image courtesy Wikimedia commons.
Picture of a Homo erectus skull on a white background. The cranium is more shallow than that of a Homo sapiens skull.
Homo erectus skull. Image courtesy Wikimedia Commons.
Though there were once many kinds of hominids, only one remains: Homo sapiens. Extinction is a normal part of evolution, and scientists continue to theorize why other hominid species didn’t survive. We do have some clues as to why some species were less successful at surviving than others, such as an inability to cope with competition for food, changes in climate, and volcanic eruptions. start superscript, 4, end superscript

Migration and the Peopling of the Earth

How and why?

Between 70,000 and 100,000 years ago, Homo sapiens began migrating from the African continent and populating parts of Europe and Asia. They reached the Australian continent in canoes sometime between 35,000 and 65,000 years ago.
Scientists studying land masses and climate know that the Pleistocene Ice Age created a land bridge that connected Asia and North America (Alaska) over 13,000 years ago. A widely accepted migration theory is that people crossed this land bridge and eventually migrated into North and South America. start superscript, 6, end superscript
How were our ancestors able to achieve this feat, and why did they make the decision to leave their homes? The development of language around 50,000 years ago allowed people to make plans, solve problems, and organize effectively. We can’t be sure of the exact reasons humans first migrated off of the African continent, but it was likely correlated with a depletion of resources (like food) in their regions and competition for those resources. Once humans were able to communicate these concerns and make plans, they could assess together whether the pressures in their current home outweighed the risk of leaving to find a new one. start superscript, 5, end superscript
Map of the world showing the spread of Homo sapiens throughout the Earth over time. Homo sapiens are reflected with red arrows (shown populating the entire world over time), Homo neanderthalensis is reflected in orange in what is Europe and the Middle East today, and Homo erectus is represented in yellow in Africa, South Asia, and Southeast Asia.
Spread of Homo sapiens. Image courtesy Wikimedia Commons.

Adaptation and effects on nature

When humans migrated from Africa to colder climates, they made clothing out of animal skins and constructed fires to keep themselves warm; often, they burned fires continuously through the winter. Sophisticated weapons, such as spears and bows and arrows, allowed them to kill large mammals efficiently. Along with changing climates, these hunting methods contributed to the extinction of giant land mammals such as mammoths, giant kangaroos, and mastodons. Fewer giant mammals, in turn, limited hunters’ available prey.
In addition to hunting animals and killing them out of self-defense, humans began to use the earth’s resources in new ways when they constructed semi-permanent settlements. Humans started shifting from nomadic lifestyles to fixed homes, using the natural resources there. Semi-permanent settlements would be the building-blocks of established communities and the development of agricultural practices. start superscript, 8, end superscript

What do you think?

Why do you think Homo sapiens is the only surviving human species?
What effects do you think the environment had on human evolution? What effects did human evolution have on the environment?
What skills were needed for human species to populate the Earth?

Want to join the conversation?

  • blobby green style avatar for user svaniksurve
    Did Hominids hunt each other? How did they interact? Is it known yet?
    (20 votes)
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    • piceratops sapling style avatar for user Joe Williams
      They hunt eachother, and still do. Since Chimpanzees are technically hominids, and have been targeted by human hunters, hominids still hunt each other. However, I assume that you're talking about prehistoric hominids, and the answer to that is that we don't know.

      There is very limited information on interaction between hominid species. Most hominids have a diet largely based on vegetables and scavenging. Active hunting is rare, and hunting other predators is extremely rare. So any conflict between hominids would be rare. Similar, it would be difficult for different hominid species to communicate with eachother, so it's unlikely that they would have cooperated with us. Humans today don't trade with chimpanzees or gorillas largely because of this extremely steep communication barrier.

      However, we do know that Neanderthals and Homo Sapiens interacted. This is evidenced by the presence of Neanderthal DNA in the genome of people of European, Middle Eastern, and Asian descent. That indicates that there was at least some inbreeding between neanderthals and homo sapiens, which suggests intimate relationships between the two groups. Beyond that, the nature of neanderthal-homo sapiens interaction is still unclear.
      (54 votes)
  • duskpin sapling style avatar for user Sushmitha Magaji
    As our ancestors didn't know how to communicate with each other, and also their brains were in the process of development, then how were they convinced to migrate somewhere else?
    I got this question because they might not be even knowing their purpose on Earth and who those other creatures were.
    I hope my question makes sense.
    (10 votes)
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    • blobby green style avatar for user Jack London
      Our ancestors did know how to communicate with each other. I believe early primates easily used body language as a start (look at modern primate studies showing complicated body language within species). (Indeed, look at modern homo's use of body language). As these primates evolved, they used their increased motor skills and memory to create sign language. Spoken 'language' was often counterproductive as it allowed others (predators) to hear you. Look at the success of modern men who are deaf but communicate easily with sign.
      There are only three truly important things in the life of a primate: food, clothing, shelter. Any one of these would encourage a clever primate to find any or all of these three. Migration is just one response to these needs.
      By the way, have you ever wondered if the migration maps are backwards? Assume the original homo line developed in Malaysia. Then the migration direction would be the opposite of the current guesswork direction. Who's to say which way/direction early homo wandered?
      (13 votes)
  • aqualine seed style avatar for user 24erlingw
    What was dangerous for the people in the stone age?
    (12 votes)
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  • winston baby style avatar for user Kindnessgirl
    On the second picture of a skull, couldn't the weird shape of it just be from weathering or decomposing?
    (2 votes)
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  • primosaur seedling style avatar for user christine.denniss
    I think when all the land masses were all together and had not separated homo sapiens migrated and whoever was on the continents when they broke up stayed on that continent. They didn't need to voyage great oceans that way.
    (0 votes)
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    • scuttlebug green style avatar for user Uma
      It's highly possible that they took advantage of when the landmasses were together, but they definitely crossed the sea to get to Australia. The fauna over there was unique and had evolved in isolation for years.
      (3 votes)
  • blobby green style avatar for user DEVAKUMAR DEVARAJA
    1.they say, many types of hominids were there but only homosapiens survived so how did the apes chimpanzeesa nd monkeys survive till to date?
    2. also if we evolved from chimpanzees why there are still chimpanzees living they all should have evolved ryt ?and there should be no monkeys in th e world
    (6 votes)
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  • starky sapling style avatar for user Carlos Baltazar
    So we all originate from Africa?
    (9 votes)
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  • mr pants purple style avatar for user Abhishta M
    so the human evolution took place in africa!
    then we all are africans?
    (7 votes)
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    • scuttlebug green style avatar for user Uma
      Well, it depends on what defines an African. If you say our origins are where we evolved from, then we are all actually aquatic creatures, living in an artificial world of dryness and too many body parts.
      (5 votes)
  • blobby green style avatar for user Sriya Lanka
    Why did humans decide to migrate? Also where does culture come into play? How did we create them? If we all originated from Africa why do we all have different tones in skin color? Did evolution have anything to do with it?
    (5 votes)
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    • duskpin ultimate style avatar for user shivali.pathak
      Good Question! The truth is, we do not know for sure whether humans were originally dark skinned. Though a theory suggests that as humans migrated to colder weather, their skin color changed as well, through evolution. Humans migrated to get away from dangerous animals that threatened their survival. Such as leopards, lions, cheetahs, and such. As for how different cultures emerged, it is a pretty big mystery.
      (3 votes)
  • aqualine ultimate style avatar for user KAMYA
    What did the people of the stone age do to cure infections, etc.?
    (0 votes)
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