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Human prehistory 101 part 2: Weathering the storm

Third in a series of videos that introduces human prehistory, this video describes how early humans continued to defy the odds and populated the Americas during the last ice age. Created by 23andMe.

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  • starky tree style avatar for user Neaera Deptuch
    I understand that the Berring Straight (sp?) theory doesn't cover all the bases. Now a days they are saying people came to the Americas in a few different ways over many hundreds (thousands?) of years. Is that just speculation? what is the current most likely path according to scientists?
    (4 votes)
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    • orange juice squid orange style avatar for user CarlBiologist
      There's very solid evidence that people crossed the land bridge that existed where there is now just the "Bering Strait." Some evidence when dated using radioisotope techniques pre-dates the spread of these peoples so there are now some theories that people migrated here using boats as well. There is difficulty finding hard evidence of this because most of the ancient coastline is now underwater. What is known with almost certainty is that the first people to populate the Americas came from east Asia.
      (11 votes)
  • piceratops ultimate style avatar for user Leandro Ricardo Batista da Silva
    What causes ice ages to occur?
    When will it happen again?
    (7 votes)
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    • blobby green style avatar for user G H
      You might want to check out Wikipedia's "ice age" for some good info on this. Historically, ice ages are caused by the interaction of many variables, like the CO2 concentration in the atmosphere and subtle differences in earth's orbit around the sun. The next ice age was not predicted to occur for 10's of thousands of years. Of course, anthropogenic climate change is really messing with the natural rhythms of the climate. Within a couple of decades there will be no arctic ice in the summer. For those who ridicule or deny anthropogenic climate change, I would remind them that 97% of climate scientists recognize the reality that humans are radically changing the climate. With all my heart I wish that they were wrong, but all of the credible evidence supports their assessment that climate change is real.
      (5 votes)
  • male robot johnny style avatar for user derick
    How do we know that homo sapiens came from Africa? Where did the neanderthals start from, if not Africa? Why didn't the Homo sapiens, along with evolution, teach the neanderthals how to make clothes?
    (4 votes)
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  • blobby green style avatar for user Nicklas Andersson
    Do scientists know WHY the ice age(s) occured?
    (3 votes)
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    • piceratops ultimate style avatar for user Just Keith
      There is more than one factor that causes ice ages. Amongst the causes are changes in the positioning of the continents, shifts in the Earth's orbit, and a drop in atmospheric carbon dioxide levels. These are not the only causes, but they are the major factors.
      (3 votes)
  • aqualine ultimate style avatar for user Josh Wasabi
    Isn't Siberia part of Russia?
    (1 vote)
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  • mr pink red style avatar for user 66916 taylor rocks
    why are the kids nude
    (2 votes)
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    • old spice man green style avatar for user Alf Lyle
      Clothing takes time and materials to produce. In a warm climate clothing serves more as an indication of wealth and status than as providing an essential need. Since children in early cultures had lower status and wealth, they didn't get the clothing. In some cultures today children often go nude and sometimes the adults as well.
      (2 votes)
  • duskpin ultimate style avatar for user charleyalexistyre
    So we're they all families once and they just got separated and started learning there own language?
    (2 votes)
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    • spunky sam blue style avatar for user YaminiAnilkumar
      Yes, we all started going our own ways and making our own cultures and religions. If this is so, we all probably all started making our own languages with our tribes/families. For example, Canadian gr 3 social studies shows the aboriginals and their tribes. They probably have their own languages too!
      (1 vote)
  • aqualine seed style avatar for user muramatsumarie
    How long did early humans take to migrate from Sibria to Alaska?
    (2 votes)
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  • leaf green style avatar for user John
    So when people crossed over to North America I always understood it was an ice bridge. This video explains that it was lower sea levels exposing more land. Which is it really?
    (2 votes)
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  • leafers sapling style avatar for user vsles
    How did the Neanderthals adapt to the cold so well?
    (2 votes)
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Video transcript

20,000 years ago, the world suffered in the depths of the last ice age. For several thousand years, global average temperatures stayed 15 degrees Fahrenheit, that's about 8 degrees celcius below what they're today, and mile thick glaciers covered much of North America, Europe, and Asia; outside the ice-covered regions, it was so dry that survival became difficult in most areas. Some areas where people'd been living became inhospitable, and in some other places, new barriers of ice or desert separated groups of people, but against all odds, some people found ways to survive in severe conditions as far north as Siberia. The ice age not only created barriers, it also created bridges with so much water locked up in ice, sea levels dropped, exposing land and connected Siberia and Alaska, a few people in Siberia took advantage of this bridge, moving into present-day Alaska, and later, down into other parts of North America, maybe they followed migrating herds or maybe, they traveled in small boats, down the Pacific coast, or maybe they did both. No matter how they got there, those people who get there became the ancestors of today's Americans. In just a short time, humans from a small corner of Africa had populated all continents except Antarctica, and in there new homes, their languages began to differentiate to form the precursors of today's languages. Some populations probably didn't survived the ice age and those that did often became more isolated from other groups, scattered around the world, these small populations became more being culturally, and genetically distinct from one another. How would cultural innovations helped a few of these groups to expand dramatically over the next several thousands years.